Hi dontworrryboutit,
Thanks for visiting Apple Support Communities.
If your iPod is freezing or restarting unexpectedly, I recommend restoring it to factory settings using iTunes. You can find instructions for restoring your iPod here:
Restoring iPod to factory settings
http://support.apple.com/kb/HT1339
Restoring erases the iPod's disk and restores iPod to its original factory condition.
Because restoring erases all the songs and files on iPod, back up any files you've saved on the iPod disk. All of your songs, videos, podcasts, audiobooks, and games can be loaded back to your iPod provided that you have them stored in your iTunes Library.
If your iPod is no longer restarting unexpectedly after you restore and re-sync it, but certain songs still skip, see this article for more steps that can help:
Troubleshooting songs that skip
http://support.apple.com/kb/TS3217
Cheers,
Jeremy