urman wrote:IBM told me that I can only restore with the original Thinkpad !

What IBM told you is right, but it's not the whole story. It's correct that the backup of the A31p's system partition won't boot up flawlessly on a T42p. But, after all, you still can restore the A31p backup to a T42p, that's possible. It just won't boot up. You could do the following:
1. Get a spare, empty drive with enough space on it, install it in your T42p, boot R&R from the emergency CD, and restore the contents of the USB drive to it. Then remove it, put the drive that came originally with your T42p back in, stick the drive onto which you extracted the backup into a USB enclosure and you'll have free access to all data. You just have to take care that you don't mix up versions: backups that were made with R&R ver. 1 should be restored with R&R ver. 1 and not with ver. 2.
2. But as you're just looking for your personal data, I guess that's not even necessary. R&R can, in fact, restore individual files and folders. Just start the Windows interface, choose the restore files function from the restore menu, select your USB drive and the backup set (usually the latest one), then mark the files and/or folders you want to restore and the location they should be saved to.
Here's the Rapid Restore 4.0 manual:
http://www-307.ibm.com/pc/support/site. ... MIGR-54504
The process is described on page 16.