I am 13 but pretty advanced.
Is Linux easy to use.
Should I buy Vista when it comes out
Or Just switch to Mac

The Answer by rajiv :

A lot depends on what you want to use the computer for. I use Linux at home and XP at work. There's almost nothing that XP can do that Linux can't. Having said that, you may run into some compatibility issues on certain file formats. Linux is good if you are looking for flexibility (also very few viruses and spywares). XP is good because it has more software (but also viruses and spyware). Mac is very easy to use, has unix at the kernel level and some nice software (but it's a bit expensive).

Coming to upgrading to Vista would depend on how powerful your hardware is. The last I heard, and I could be wrong, is that Vista would require at least 512 MB of RAM — read 1GB if you are looking for some speed, and also much more processing power. As for me, I plan to stick with Ubuntu Linux at home for some time and if I decide to switch, it would be Mac.