Perhaps the biggest gripe about Linux is the lack of games. Linux has a much smaller share of the desktop market when compared to Windows. For most game companies, it is not profitable to make native Linux versions. Don't despair, there is hope.
With a nifty program called WineX , you can run some Windows games inside of Linux. A complete list of compatible games is here . Be advised, that WineX requires a modest "subscription" fee to download.
A few games have been made available in native Linux format, meaning they don't require WineX or any other emulator to run. Two recent examples are Unreal Tournament 2004 and Neverwinter Nights: Hordes of the Underdark. If you like flight simulators, FlightGear is an excellent and FREE simulator.
Switching operating systems is a monumental task, and not everything will work correctly on the first try. Linux offers you complete control, but that control can be confusing and downright alien to Windows users. It takes a while for people to adjust to their new found freedom, but I hope you will find Linux to be a very flexible and promising operating system.