I owned a iPod nano, but I recently returned it and bought myself an iPod video. I've owned many other mp3 players as well, from Sony, MPIO, to Philips, but I must say the iPod is the best player in terms of design and ease of use.
Yes you can put video files from your PC onto the iPod. There are many free converters out there (just google them). Although from my experience it does take a while to convert, depending on how old your PC is.
I highly recommed a case or at least something that protects the screen. Deep scratches shimmer the screen and can ruin your video watching experience. In case you didn't know the battery life for videos is rated at 2 hours, so if you care a lot about video I'd recommend shopping for other brands.