its up to personal opinion but GTA 5 is newer and i personally like it better
gta 4 is way better then gta san... i'd say gta 4 is better.
Call Of Duty 4
Yes. Some of them will be there just like that guy from GTA 3 was in GTA:SA...
No even GTA 4 was not on PS2 when GTA 5 is released it will not be on the PS2