And the i-pod shuffle has a nifty little clip ;)
But i wouldnt get it as it has no screen.
Go for nano or classic, and Pug, my I-Pod Nano (2nd Generation) is a 4gb.
It really depends on how much you will use it or how much you are into your music. The more you pay, the better you get although the Nano really is a very good gadget at a low price.
If your into your music, but dont think you need to splash a fortune for high storage, go for the Nano. If you will need that extra space for more songs, big up the Classic.