Tekken 5 for me.

I prefer 2D fighters personally, but there are some decent 3D fighters out there.

For me my favs are:
2D: Marvel vs. Capcom 2 and Samurai Showdown
3D: Soul Caliber 2 and Narutimate Hero 2

The best 2D fighting game I have ever played would be that one inuyasha game. The best 3D fighting game I have played would be bloody roar 3.

2D = All the KOF series and Guilty Gear.

3D = DOA series, KOF max impact and Tekken Series.

The best one hu.............hm let me think.Guilty Gear X Reloaded for sure.
This Game beats every other 2D Fighting Game^^

The Guilty Gear, Soul Calibur & DOA series are great ! DOA's the greatest.

2 best fighting games in my opinion are both 2D :
ggxx Reload
SF 3rd Strike
I don't play 3D fighter seriously, but If you ask me, It would be Tekken 5.
The game's graphic is awesome.

Dead or Alive series (nuff said )

Guilty Gear X2 wins hands down. The gameplay mechanics is more complex than most other 2D fighting games.

Soul Calibur 2 for 3D fighting games. Not really into Tekken.

2D : Street Fighter 2 Turbo.
3D : DOAU or Soul Calibur II (the GC one)

2d - ggxx
3d - tekken series

2-D...least I think it is...
Super Smash Brothers melee!!!! YEAH!!
3-D
Soul Calibur II, but i know Soul Calibur 3's gonna be way better.

As far as 2D goes, maybe Capcom VS SNK 2
3d, probably Tekken Tag Tournament. It was just so fast and brutal (not in the MK way though8P) that once you get a battle tactic down, it'll almost never fail you...I think my ultimate team was Jin Kazam and Nina Williams

2-D - Capcom vs. SNK 2 EO
3-d - Soul Calibur II

kof series-2d
i don't like playing 3d fighting games

2d: 1) Guilty Gear series
2) Marvel vs Capcom series
3) Mortal Kombat 1,2, and 3

3d: 1) Dead or Alive series
2) Soul Calibur 2( X-Box version. Spawn is way cooler than Link and Heihachi)
3) Power Stone series ( A great game on perhaps the best system, the Dreamcast)

2D - the King of Fighters series
3D - Soul Calibur II

My favorite 2d fighting game is Darkstalkers 3 and my favorite 3d fighting game is the DOA games.

2D:Guilty Gear Isuka
3D:Dead Or Alive 2 U

2D) Guilty Gear
3D) DoA

I don't play 2D games, but I play: Soul Calibur 2, & Dead Or Alive.

2D - maybe Capcom VS SNK 2 (PS2) or Super Street Fighter (Genesis)
3D - Tekken Tag Tournamenrt on PS2...hadn't had that much fun with a fighter in a LONG time (haven't touched them for quite a while now)

2D - prolly Guilty Gear series and Marvel vs. Capcom 2.

3D - i'd have to say the Soul Calibur series (i guess this could include soul edge as well)

2d

king of fighters
street fighter
mortal combat

3d

rival school series
tekken series