i want something Actiony Massively Multiplayer and Free, something with Gunz-style gameplay but Roaming would have been awesome.

Games i liked:
Gunz Online (Very fun and great action)
Ragnarok Online (i have a soft spot for that game, played it many times)
NexusTK (Very nice game, too bad it's P2P)
Unreal Tournament (Really nice game)
Pangya (Well, not actiony at all but i liked it)
PSOBB (Great game i gotta say, but it's really hard on low levels)
plenty of more i cant remember.

"Ehh... Whatever i'll play it for a while" Games:
Maplestory (it's ok, i came t0 lvl 15 when i noticed that there is no real goal in grinding, no PvP, no nothing.)
MythWars (i liked it at the beginning, but it got boring very fast)

System Specs:
2.0GHz Intel Pentium 4
1GB Ram
NVidia GeForce 7600GS (256MB)

Please i am Desperate!

EDIT: i also really like PvP
EDIT 2: it would be awesome if it had custom weapons XD