When I connect my iPod touch to my windows it doesn't appear as an available device, and it appears to be charging.
iOS: Device not recognized in iTunes for Windows
I would start with
Removing and reinstalling iTunes and other software components for Windows Vista, Windows 7, or Windows 8
Removing and Reinstalling iTunes, QuickTime, and other software components for Windows XP
Run this to help if it identifies the cause
iTunes for Windows: Device Sync Tests
Have you tried on another computer to help determine if you have a computer or iPod problem?
Retrieving data ...