I have movies, TV shows, Podcasts, and music on my iPod.
I have more media than I have battery life to enjoy.
I also have a car charger, and a wall charger.
I also have a device that allows me to hook up to a TV and play my movies on the TV, whilst recharging/maintaining a charge on the iPod.
Yes, you do have to have iTunes to load music, but you don't HAVE to buy your music from them.
Most of my music is from the many hundreds of CD's I have lying about the place.
There is also a pretty active indie/podcast crowd. The only downside to podcast music is having to listen to the 30 seconds of advertisement crap at the beginning or end of the songs.
I have like 15-20 movies on my classic, over 2000 songs, and a crap-ton of other stuff.
I also still have over 50GB of free space.
What ever you get 80GB should be PLENTY of space.
If you drop the big bucks and get a iPod Touch you have a bigger screen to watch stuff on. And 32GB is a good bit of space to store anything you need for at least a week worth of commuting before having to do some "file management". Hell, I've got over 300 podcasts on mine that include podiobooks, music, car reviews, and guitar lessons.
The ZUNE, is an okay device, and has some cool feature. However, if you share a song from a friend, you do get that song for free. But you can only play it 3 times and it's gone.
iTunes can be a pain in the ass if you buy any amount of video, or download any of the free video that isn't podcasts.
It will require you to update to the newest version, and Apple updates pretty damn often.
Either way. If you can find a way to play with each of them for a while, you can find out what you like and what might annoy the holy hell out of you.