How old is your Ipod Classic? My guess, especially since it got "stuck" while sync-ing, is that your Ipod may have had a hard disk problem.
Did you reconnect it to Itunes? Did it display any warnings or behave differently? Did Itunes tell you it was rebuilding anything? Did putting your music back on the Ipod work?
Small problems are not necessarily anything to panic about, but hard disks don't last forever.
Edited by Capn Easy, 16 July 2010 - 02:16 AM.