It's possible to see the files and access them if you are still using a 2000 Pro operating system(OS), but with the new XP OS on your new computer, I don't think you can access those files again. Unfortunately you have to reformat the hard drive to XP platform and loose those files. Unless you can hook it up to another 2000 Pro OS to access those files and save them onto a disk. However, that might not work either, since your hard drive is acting as a big "floppy" disk when you hooked it up to your new computer XP OS, so the CD you saved the 2000Pro files onto is just like that big "floppy", it may/may not work.
If you did have 2000Pro OS installed on the Maxtor HD, then you definitely cannot access those files!! So a CD might actually work:)