Battlefield 2 vs Counter-Strike: Source
Battlefield 2
Battlefield 2 is one of the Battlefield classics and rightly so. The game lets you play as a soldier in one of the three major military superpowers: the United States, the Chinese or the newly-formed Middle East Coalition. Players will have access to a wide range of weaponry to do battle with as well as a variety of vehicles. Similar to the original game, the game has a large-scale multiplayer mode - the hallmark of any game from the main Battlefield series - that can accomodate up to 64 players on a single map.With more weapons and vehicles for you to play with, Battlefield 2 is a pretty nice sequel to the Battlefield franchise. However, considering that it has not yet been reworked, unlike the first Battlefield, and that currently, there is no way you can purchase the game unless you get the hard copy off eBay or a similar site, you might be better off buying any of the other Battlefield games.
Counter-Strike: Source
Counter-Strike: Source is the second installment in the incredibly popular MMOFPS franchise, Counter-Strike. Despite being a rather old game, Counter-Strike: Source still manages to hold its own in this day and age, with some even claming this game is so much better than the more recent Counter-Strike: Global Offensive or CS:GO. Unlike CS:GO, this game doesn't offer buyable skins and the most important thing - the community is definitely not as toxic as those you'd find in the CS:GO servers. Although the game modes can be rather limited, you can easily find some really good new ones in modded servers.So, if you're looking for the Counter-Strike experience without all the hate that most new players will get, this might be a good game to start.