Hello there Tonyal8507,
I was researching what might cause performance issues with iTunes on a Windows computer and found this lil gem. Named Apple software on Windows: May see performance issues and blank iTunes Store, found here http://support.apple.com/kb/ts4123, I think it will help you out.
If that troubleshooting does not resolve your issue, you may want to consider recreating your iTunes library.
iTunes: How to re-create your iTunes library and playlists
http://support.apple.com/kb/ht1451
Regards,
Sterling