PS2, Xbox and PC all use IDE spec Hard Drives.
You can mix and match them all you like, but each is formatted with their own file system, meaning they can't see each others contents, for example, a Xbox cant see a PS2's files.
Provided you format them, you will in business.
Xbox HDD's have an extra layer of protection. You must 'unlock' the drive before it can be used. Config Magic can do this in a few seconds, BUT, it MUST be done on the Xbox it came from, as that is the only xbox that has the matching key.