My Ipod touch 2g wont sync with itunes and itunes wont close

Itunes wont recognise my Itouch (2nd gen, 16gb,ios 4.2.1) and wont sync. It occasionaly finds the ipod but doesnt sync and freezes whil displaying a rotating beachball symbol next to the device. It does not load from then and does not reach the itouch mangement screen (where you can sync, update,restore..) Occasionally when it does load up like normal or start to sync it gets stuck on syncing/verifing/backing up and gives the error iTunes was unable to load data class information from sync services' in which i am unable to attempt to reset sync history as itunes crasheswhen prefrences is clicked to open. While any of these proble occur itunes will not close properly (when the red x is pressed at the top right), i have to go through task manager.

I have :

windows 7 ultimate 64

Itunes 10.6.1.7

Itouch 2nd gen 16gb IOS 4.2.1

Thanks in advance