After working for years, cannot get Windows started

Using Parallels to run Windows XP inside my iMAC, I get the following error mesages:

1. Unable to connect to Hard Disk 1
2. There is no Operating system installed in this VM. Please insert CD & restart.
3. 3. on inserting CD, os does not run giving error message: "only runs in a system which is Intel based!!"

Have tried deleting Parallels and Windows and reinstallinh using Time machine, but problem persists.

Any ideas?