You want to use the same Apple ID on the iPad as you use on the PC. Your Apple ID should be your main email address.
You use your Apple ID for purchases, iCloud , iMessages and FaceTime, if you have been using this Apple ID on your PC, continue to use it on the iPad. Don't use the new ID. Purchases are always tied to the Apple ID that was used to make the purchases. You don't want to have two Apple ID's.
Go to Settings>iTunes and App Store>Apple ID. Make sure that you are signed into the same ID that you are using on the PC.