Opening a new iTunes window for my apps (Windows 7)
Certainly, deleting your iTunes library on your computer, then just syncing your iPad back to your computer would be the most ideal solution. There is no way to access old versions of iTunes when things weren't synced as they are now so the way you described isn't possible. However, as long as you have all of your stuff from your computer, then deleting everything there and just keeping the stuff from your iPad is probably the best solution. Sorry if it's not what you wanted to hear.