I've still got a CorelDRAW 3 somewhere.
Right, in those days programmers did not make an uninstal routine.
What I did was delete the directory is was in (I think it defaults to C:\Corel).
I then ran Registry Mechanic (Norton SystemWorks would do) which picked up the odd dll which was lurking in windows.
It don't half move quickly in XP doesn't it. Problem is it looks SO old. I remember it when it was new - the BEES KNEES. Totally eclipsed by CorelDRAW 4 (I think they're on 12 or 13 now).
Good luck - it's not the worst thing in the world just to leave the other odds and sods, but were it me, I'd run sfc /scannow afterwards to make sure Corel3 hasn't run off with anything it shouldn't have.