Here's my personal opinion about Dream Theater's discography, with all the albums by the American band (excluding EP's, compilations and live albums) ranked from worst to best. Of course, this is only my opinion, so please don't get angry.
Ok, let's get started!
The astonishing (2016)
Top tracks: track 57 and 324, I think.
Dream Theater call it "The astonishing".
In reality, "astonishing" were the yawns I made while listening to this work in its entirety and in the magnificence of the 34 tracks unrolled in 2 hours and 10 of total duration. Brie plays 124 characters, Petrucci stays in the little bar under the recording studio for long stretches and Rudess plays piano for 2 hours. There are also great moments and beautiful songs, but rather than listening to it all in its entirety I prefer to go and join Petrucci at the bar, ordering the worst possible beverage.
Rating 48/100 (for the effort)Top tracks: track 57 and 324, I think.

When dream and day unite (1989)
The debut. Oh, these guys really know what to do with instruments, too bad Dominici's voice isn't exactly the best and he also seems to be singing from the sewers. I don't think I've ever been able to listen to it in its entirety because I just can't stand it. I give it a chance every year, but nothing so far.
Rating 52/100
Top track: Ytse jam, A fortune in lies.
Black clouds & silver linings (2009)
The band seems to have lost inspiration at this point of their career, apart from the beautiful The count of Tuscany (what a thrill to listen to it live!). The Brie seems to be singing on autopilot and feels like he learned the vocals 10 minutes before he went to record them. Or maybe he recorded them improvising, I don't know. Luckily I bought the special version with the second cover disc which is much nicer than the record itself, there are covers by Queen and Iron maiden, nice!
Rating 54/100
Top tracks: The count of Tuscany and the bonus disc.
Skip tracks: Too many.
Skip tracks: Too many.
Distance over time (2019)
The band returns to more appropriate tracks and leaves the sofa, the herbal teas and the yawns of the previous album The astonishing. The production is great and Mangini/Petrucci plays amazingly together but LaBrie's inspiration is at an all-time low and the vocal lines of the album are almost illegal.
Rating 57/100
Top tracks: Fall into the Light, At Wit's End, Pale Blue Dot.
The band returns to more appropriate tracks and leaves the sofa, the herbal teas and the yawns of the previous album The astonishing. The production is great and Mangini/Petrucci plays amazingly together but LaBrie's inspiration is at an all-time low and the vocal lines of the album are almost illegal.
Rating 57/100
Top tracks: Fall into the Light, At Wit's End, Pale Blue Dot.

A view from the top of the world (2021)
I quote some of you: "never heard such an effort to say such so little". The album has a great sound and the usual amazing performance by the band (even LaBrie sounds more inspired!), but I find the songs are very stretched, in my opinion, and the album is too long for the ideas in it.
Rating 62/100
Top tracks: Answering the call, Invisible monster, The alien.
Top tracks: Answering the call, Invisible monster, The alien.

Six degrees of inner turbulence (2002)
A double cd, the first one with 5 heavy meatballs to digest (actually 4, I like "Disappear", even if it's a little heavy as well), the second with a great mini-suite. If they had spared us the first CD it would have been better for everyone, unfortunately they didn't. Yet it started off very well, at Petrucci's first super riff, one of my favourites..
A double cd, the first one with 5 heavy meatballs to digest (actually 4, I like "Disappear", even if it's a little heavy as well), the second with a great mini-suite. If they had spared us the first CD it would have been better for everyone, unfortunately they didn't. Yet it started off very well, at Petrucci's first super riff, one of my favourites..
Rating 66/100
Top tracks: The second disc
Skip tracks: The first disc
Octavarium (2005)
Portnoy takes over the band by forcing others to release songs about him, writing songs inspiring from bands he likes (who said Muse?) and even singing more and more. I walk beside you seems like a piece taken from U2's discography. Not a brilliant record, apart from the title track, which is a semi-masterpiece and fortunately lasts more than 20 minutes. Listen to it, it's an interesting experiment, it always builds up and it never goes back.
Rating 67/100
Top track: Octavarium, The answer lies within.
Skip tracks: These walls, Never enough.

Train of thought (2003)
One of the darkest and heavier works by the band. The band got into the bad habit of only writing long pieces without having early career ideas and Portnoy starts being a little too present, ouch ouch ouch. Nonetheless, it was the perfect album for my afternoons on Burnout (the video game). I remember it positively enough for that, isn't that a good enough reason?
Rating 67/100
Top tracks: As I am, Endless Sacrifice.
One of the darkest and heavier works by the band. The band got into the bad habit of only writing long pieces without having early career ideas and Portnoy starts being a little too present, ouch ouch ouch. Nonetheless, it was the perfect album for my afternoons on Burnout (the video game). I remember it positively enough for that, isn't that a good enough reason?
Rating 67/100
Top tracks: As I am, Endless Sacrifice.

A dramatic turn of events (2011)
Portnoy: "Guys, why don't we take a break to get some new inspiration?" Petrucci: "You're out of the band". Historic record as the first without his main member and with Mike Mangini in his place (the DVD of the auditions for the new drummer like a soap opera is included in the special edition). The album is ok, but it was cleverly "copied" by Images & words: all the structures (apart from Beneath the surface) belong to that magnificent album. Without the inspiration of those times and with a Labrie being a distant relative, of course. Mangini is doing well, all things considered. The cover sucks a bit.
Rating 67/100Top tracks: Lost not forgotten (Under a glass moon), Breaking all illusions (Learning to live), Beneath the surface.

Falling into infinity (1997)
The record company sees the DT's potential in terms of selling and ask them to do a lighter and more radio-friendly album. The band is confused and doesn't know what to do, the result is a hybrid work, many good songs, many softer songs and a lot of confusion. Kevin Moore said he wasn't interested anymore in heavy music and his replacement was the shy Derek Sherinian, who probably introduced himself with a fluorescent purple dressing gown and a rapper-style gold necklace.
Rating 69/100
Top tracks: Peruvian Skies, Hollow Years, Lines in the sand.
Skip track: Burning my soul.

Dream Theater (2013)
This is the first real album without Portnoy and with Mangini at full capacity.
The structures, how much I love them! In this record, there are: intro, an instrumental and also a final suite, exactly as I like it. There will be no masterpiece inside, but overall this Dream theater is enjoyable, extremely enjoyable, so much so that I listen to it very, very often. Maybe too much. Rating 71/100
Top tracks: Enigma machine, The bigger picture, Illumination Theory.

Systematic Chaos (2007)
Not really recognized but I really like this one. Portnoy again superstar (too much, maybe) and Petrucci in a horror version. Don't ask me why, but it all works. I understand that it's not a masterpiece but (almost) everything is in the right place at the right time. The documentary DVD attached to the CD is beautiful too. Forsaaaaaaakeeeeeeeeeen
Rating 77/100
Top tracks: Forsaken, The dark eternal night, Repentance.
Put it this way: the only bad thing about this album is its predecessor (see next position), which is a total masterpiece. Awake is a hell of an album but a little less inspired than Images and words. Wait a second, am I really complaining about Awake??? Ok better to shut up.
Rating 84/100
Top tracks: Erotomania, Voices, The mirror.
Rating 84/100
Top tracks: Erotomania, Voices, The mirror.
Images and words (1992)
After the debut album, Dominici was kindly escorted out by Portnoy and Petrucci's Rottweilers and LaBrie is let in. What comes out is an absolute masterpiece, Petrucci is considered new messiah and DT goes from complete strangers to world stars with just one record. And what a record. I still remember like it was yesterday (it was 1993, I guess) clicking play on the cassette for the first time, knowing nothing about the band. Perfection.
Rating 100/100
Top tracks: All of them
Top tracks: All of them

Scenes from a memory (1999)
The band decides to abandon the shy Derek Sherinian for Jordan Rudess and not to listen to the label anymore after Falling into infinity. The result is a perfect concept album in every second and in all respects, once you hit play you're screwed, you have to listen to it all. I have a rare copy with a "scratch" at 0.36 from the fifth song. Yes, I know, you don't care. Scenes from a memory to me is the best record ever. I can't understand how my copy still works, I've been listening to it non-stop for a couple of years.
Rating 100 + and cum laude too.
Top tracks: If you are looking for top tracks you didn't understand.