Partition magic is simple to use but is also limited. Once it encounters a problem it refuses to carry out any work on the drive.
I understand that there is a 'pro' version of it available that will allow you to attempt to fix partition problems. A lot more expensive though!
'Diskdrake' from Mandrake is free (!) & nearly as simple to use as Powerquest's product. As long as you have a bootable Linux disk eg the Mandrake Linux install disk then you have ready access to Diskdrake.