Buddy , I'll put my money on GMA 900 . But as he said it lacks pixel shader 2 which is required in some games. But also GMA 900 is much newer and it supports dx9 . I think this choice requires us to know what the CPU RAM and mobo are ??
Definitely not GL ( doesnt have some features , my mobo 915GL doesnt have raid . i dunno whether it is company or chipset feature itself ).Check the intel site . Also decide ur mobo. I should see teh diff b/w G & GV.
If u find it post it.
I think u better think of AMD and u may go for 945 as they have i gma950. which has pixel shader 2 and etc..