I haven't tried the unsafedisc (ver 1.5.5) under xp so I don't know if you are right or not....
But removing sd1 is rather easy and you can learn something from it.
The difficulty of cracking depends on the protection of course, but if you are really interested you should start the easy parts (cd-checks, safedisc 1

). You are not learning anything with automatic removers.
Btw, installing 98 and xp on one hdd isn't any problem. But maybe a 3rd party boot loader is the better choice
Just my 2 cents....