Community wise BF2 is pretty big, but I've never had worse problems with admins in any other game compared to it, not even close.
If you are able to fly a jet and ever even consider killing an admin, chasing down a jet towards their aircraft carrier when it's almost dead, dropping bombs on a white flag, or accidently smacking into a helicopter you will be kicked / banned.
1942 takes a LOOOOOONG time to get used to namely for the command menu.
2's command input is alot simpler than in 1942
Vietnam is pretty much 1942 with a better graphics engine.
can'tsay anything about 2142