You will be amazed...
Where anyone can just take up a controller, find a weapon that looks pretty cool and jump into the game head first and still manage a few kills on Halo, Ghost Recon 2 demands patience and experience. While Halo's control scheme is pretty straight forward, anyone can get into a full out bloody battle, that of GR 2 has a much more complex control scheme.
A sharpshooter can actually go 'camoflouged' and get a few decent kills with 'camping'. It's not a cheap move. In a war, there are such things as snipers. Deal with it.
I strongly recommend Ghost Recon 2 if you're quite big on multiplayer LAN experiences. Rent a few copies, or buy one for yourself. You're guaranteed a good time.