I have a pink 2nd generation iPod nano, and I really like it! It holds up to 1,000 songs, but that depends on how long each song is. The battery lasts quite a while, and is very reliable.
And like Alyssa, I also have the 1st generation iPod Touch. I like this one too, but the battery lasts half as long as my nano!
The iPod touch is pretty much the iPhone, but without the phone, texting, and camera portion.
Good luck with your decision!