What linux to use (+ questions)

What version of linux should I use for my desktop pc?
I know literally nothing about linux, but ive decided I may aswell try it out.
What version of it should I use? preferably 64 bit.  

But yeah, I know nothing about it, just want to try it out, anything you guys recommend I do on it?
Thanks for any answers! 

Edit: will be running on one hard drive, alongside windows 7, just wondering, how would I switch between the os', does it show up when I boot? Ive never used anything other than windows >.> 

For first-timers, I recommend Ubuntu. Easy to install, and great support. You can install beside Windows 7 and choose it upon boot.

ah ok. Ill try it out later.