I have one of the old ipod nanos,
the model before the new ones with cameras.
It's pretty simple, you just have to get used to the circular navigation thingy, lol.
They should be pretty decent price now, since the new models are coming out (or are already out?)
They're a nice small size, so you can just put them in your pocket,
but they do scratch pretty easily, i had to get a case for mine.
That is assuming that you don't want a model with a camera built in,
however I'm not sure how high quality the camera is, and i figure
if you have a good camera anyway it's kinda pointless.
** Also assuming that you dont need like 10000 songs on the thing,
an 8 or 16gig nano should be fine. Apparently you can fit 2000 songs on an 8gig ipod,
assuming that its just songs and not movies.
And lastly - it depends. An Ipod shuffle is alright, except you cant choose a song if you want to listen to it,
you just have to hit next and hope you get lucky, that's why i prefer the nano.
Sorry to rant on, I hope that helps