I've never had a data loss of any kind with Partition Magic in hundreds of uses and that's the best bet for this job. Version 5 was issued free on some magazine discs around a year ago. Also, the rescue floppy discs that are created during any Partition Magic installation will run on any computer with a built in floppy drive and will work for any Windows version.
As an alternative, the current Personal Computer World magazine CD 1 has Partition Expert on it. This is an Acronis utility which works well but is slightly less easy to use than Partition Magic, but not too difficult.