Battlefield 1942

 
In Battlefield 1942, you can fight offline with decent but unspectacular computer-controlled bots. Online, you can play in four different game modes against up to 64 players at a time. Realistically, you'll usually find servers capable of handling only 32 players, at most. Even with that reduced number, and even if you have the game's first patch installed, have a cable Internet connection, and get a ping in the 50s or 60s, there's a good chance you'll experience some lag or choppiness. Trying to shoot bazookas at tanks, which will suddenly appear elsewhere because of lag, isn't exactly enjoyable.
 

Battlefield 1942 can be a lot of fun things to a lot of people, but first it's important to tell you what it's not: The game definitely isn't a realistic WWII combat simulator. This is a pick-up-and-play action extravaganza, a comic book version of WWII. The fact that any player can casually hop into a tank, drive around, hop out and pick off an enemy soldier with a sniper rifle, hop into a plane, parachute out, and then call in artillery fire (within the span of a few minutes) should tell you a lot about the game--and a lot about what makes it so much fun.