Well you definately won't be dissapointed in the switch, Linux is alot 'cleaner' than any version of Windows you can get your hands on. With what you said you're gonna use the computer for you shouldn't have any problems getting used to it, but be warned about the Online game thing. Linux is not really an OS for a PC gamer, lots of games will not run on Linux and once Windows is gone, if you have a problem you'll have to start from scratch to have fun again.

*note to self: If I had a really fast and reliable computer I would run Linux and play PC games in a Windows XP virtual machine via VMware.