Hey all. I'm getting the itch to play an RPG again but I feel a bit burnt out with the ones I've already played and I'm looking for something new. Here's all of the RPGs I've ever played that I enjoyed. Any ideas?

Baldur's Gate 1 and 2
Icewind Dale 1 and 2
Planescape Torment
Jagged Alliance 2
Deus Ex
System Shock 2
Fallout series
Elder Scrolls series
Anachronox

I've tried NWN series but I'm not really a fan and I don't think I'd really be into the Ultima series.

Divinity Series. You can start directly from Divinity: Original Sin, since it's a prequel. And it's a masterpiece.

Temple of Elemental Evil is one not to miss.
Spiderweb RPGs are heavy with story and choice, but weaker on gameplay and art. But still strong enough to be amazingly fun. They can absorb time like a sponge.
Witcher (I've still only played 1. It's built on the engine of NWN, but plays closer to Summoner on steroids and with great story elements)
Betrayal at Krondor (plays like reading a book in many ways)
If you give it some time, the Dark Eye Realms of Arkania games will probably grow on you.
And, of course, don't miss Drakensang. I've only played the first, but I can recommend that one too. It's a really, really good game.

I got some more Isometric PC RPGs to recommend and some of them include Action RPGs if you don't mind:

Arcanum
Divine Divinity and Beyond Divininy
Temple of Elemental Evil
Diablo 1 and 2
Sacred 1 and 2
Nox
Heretic Kingdoms
Lionheart Legacy of the Crusader.

Older DOS RPGs:

Might and Magic
Ultima (start with 4 since the canoncity of the first 3 games loose)
bard's tale
Wizardry.
Wasteland 1

Newer AAA RPGs
Dragon Age: Origins
Dragon's Dogma (Console Exclusive)
Demon's Souls (PS3 EXCLUSIVE)
Dark Souls 1 and 2

Newer Indie RPGs.

Divinity Original Sin
Torchlight 1 and 2
Wasteland 2
Path of Exile
Shadowrun Returns and Dragonfall.
And of course the upcoming Path of Exile and if it ends up well Torment Tides of Numenera.

Arcanum
Knights of the Old Republic
and since you already have NWN (but apparently didn't like it), you should probably try to salvage that purchase by trying The Prophet.

You should try the Gothic series.

If you don't dislike anime style art, I really suggest you to try Septerra Core. Loved it, also had the chance to chat a few times with one of the devs a few years ago, too bad about Valkyrie and the sequel tho, and I believe Zuxxes still sits on the title ownership without willing to do anything with it, or allowing it to be sold to someone who would do something with it.

"Septerra Core" is pretty linear but has an amazing, rich setting, great characters, music, and story. One of my most favorite RPG-s even today.

Also, consider playing "Neverwiner Nights 2", if you don't want to skip NWN1, I suggest only for the mods and if I recall correctly, the last expansion. The NWN games shine best if you play the community created mods. I suggest you check out the top 10 mods for both games.

If you like steampunk, play Arcanum, it is similar to Fallout 1/2 in some ways. A bit buggy, but the art is pleasant.

"Vampire: The Masquerade - Bloodlines" is great if you like White Wolf's dark world, or if you just like vampires in modern setting.

Deck 13 released a somewhat less known RPG, focusing on story and one of the rare few games that has a female protagonist. The game is called "Venetica", compared to most games on GOG it is pretty/new. Getting used to controls may take a while, but its worth it.

If you didn't play them yet, play the "Dragon Age" and "Mass Effect" games. I love Dragon Age 1 (origins), and I think I prefer Mass Effect 1 to 2 as well.

Jade Empire is a must, not for the clunky combat, but the amazing story and companions.

"Knights of the Old Republic" 1 and 2, might be worth for you even if you don't like the Star Wars setting.

The "Age of Pirates" games should help you calm your piratey plundering and sailing lust. They have also epic music.

"Alpha Protocol" is an espionage/action gem from Obsidian that is way too underestimated. Comparing to most games on both our lists it is also quite new.

Just as Septerra Core, if you don't dislike anime style art, I highly suggest "The Last Remnant".
The English voiceover/subs are however extremely inaccurate translation of the original Japanese, makes you really hate the main protagonist, so if you know a bit of Japanese I suggest to change to the original Japanese voices in the options.
The world is pretty unique with absurd creatures, some interesting characters, the story is very long, the character classes of you and your companions are chosen based on used skills instead the other way around (like: you use certain melee combat type a lot and also magical healing then you are likely to turn into a cavalier/paladin)
You will enjoy this the most if you love anime, and know some of the "typical" story elements in the genre (like what "tsundere" means, or what Japanese idols are), in case you are not on good terms with this kind of style I highly urge you to rather avoid it.

"Hard to be a God" is unique in its own way. I believe it is a Russian-made game.

and then there is a list of games from Spiders, I can suggest you pretty much all their games released till this date:
"Faery: Legends of Avalon" (a fantasy game from the unique perspective of playing as a tiny fairy, you customize the main character)
"Of Orcs and Men" (the protagonist is an Orc and has a Goblin sidekick)
"Mars: War Log" (The flavor of the setting is similar to Fallout)
"Bound by Flame" is their newest game, and the only except Faery where you can customize the looks of your main char to a certain degree.

All of their games have some bugs, but they are usually refreshing in their own way.

"Divinity II: Developer's Cut" Has pretty graphics, a decent storyline, and gives you the option to play a character that can turn later into a dragon and have a keep you can modify and upgrade. From the same creators comes "Divinity: Dragon Commander" (2013) and "Divinity: Original Sin" (2014), I suggest you avoid the prequel games before Divinity II though, unless you like Diablo clones. "Dragon Commander" is a hybrid between strategy and RPG, but I suggest it to you due to the political story aspect which I found highly enjoyable.

"Two Worlds 2" has its bad and good sides, still worth a look, especially the later pirate expansion. Extremely high quality character creator, takes a while to make the good faces if I recall though, and you end up with pretty ugly faces if you only use randomizer. Has an unique multiplayer-only part that is worth looking into where you have your own town, avoid the prequel though.

I am very sure I missed quite a lot on the list, but these will occupy you for a while I'm sure.
My own Top 3 Suggestion for you would be Jade Empire, Dragon Age 1, Septerra Core :)

Surprised noone mentioned the Eschalon series ( unless I missed it)

Have you tried the total conversion mod Nehrim for Oblivion? I'm currently playing it and I enjoy it a lot. It's got a setting independent of TES, hand-built landscapes and dungeons, and somewhat different level-up mechanics similar to the Gothic series (xp, no level scaling, skillpoints to be spent at trainers), but it's not as hard.

Extremely kind of you sir, in his place I would go for it :)

Too bad about Troika btw.

I am myself interested in Dragon Age 3 right now but ofc no way will anyone make a giveaway for that yet, for quite a long time. Also, a lot of people report dozens of bugs so waiting a few patches may be good anyway.

Thanks a lot everyone, especially to joriandrake for going to all that effort and for the kind offer from ChaunceyK. I went with Arcanum (before I saw the offer ha!) but I didn't know about the patch. I'll get it patched and start again. I got killed by a wolf 30 minutes in anyway! Cheers!

Should I download both of these for Arcanum?

http://www.terra-arcanum.com/downloads/arcanum/fixes/UAP091225.exe

http://www.terra-arcanum.com/downloads/arcanum/hacks/arcanumEquilibriumRebalanceByLeonidusxV1.12.zip

Definitely Arcanum
You might give Shadowrun returns a try and especially Dragonfall.

You're welcome.

As for community mods and later patches, I can't help you there as I last played Arcanum when Troika (the developer) still existed.

Just here to add one more vote to Vampire The Masquerade: Bloodlines. It's the third (and final) game made by Troika Games and it's widely considered to be one of the best roleplaying games ever.

It features multiple playable clans (sort of like races in most games), each having a unique twist in terms of ability and dialogue. While you'll be doing the same missions every playthrough, you'll get several unique playthroughs out of it because it really allows you to complete missions however you went 90% of the time. Like to sneak? Good for you! Stealth is a very viable MAIN playstyle in Bloodlines. Wanna fight? Hey you can do that too, do you wanna specialize in sharp sticks, boomsticks or your fangs? Wanna talk your way into and out of situations? You can even do that on a fairly regular basis.

Dialogue is a HUGE part of Bloodlines and it's extremely well written and mechanically sound. Dialogue choices work right into choice and consequence, insult somebody and they're liable to A: not give you a quest or B: send you on a quest and then stiff you on the reward or even C: refuse to talk to you ever again. On the other hand if you sweet talk somebody then you might just get some extra rewards and valuable info. Speaking of choice and consequence, it's a major part of the game and sometimes it takes a while for you to realize the ramifications of your actions.

I mentioned earlier that each clan has a unique twist, it's not just a visual twist with slight stat and special bonus changes. Malkavians for example are completely insane, not only do they say insane things but even the font for their text is weird. For another example, Nosferatu are physically deformed and have to avoid being seen by humans so you'll be traveling via sewer more often than not.

Long story short, it's my favorite game of all time and I completely 100% recommend it. It has a rep for being buggy but it's bugginess is vastly overstated and there are new (unofficial) patches coming out as recently as a few months ago.