I want you to start over.
Get a hold of (or download the file) a W98 (or ME) boot floppy. Delete drivespace and add debug.exe to the diskette. If you have to download debug, you need version Dos7 to go with 98 (or Dos8 to go with ME).
You are going to completely blank the first cylinder on the hd with debug.
Pop in the floppy - restart - at the "A" prompt, type debug. You will get a minus sign prompt ( - ). Type in the following lines, hitting Enter after each one. There are letter O's only in the word mov.
f 200 L200 0
a 100
mov ax,301
mov bx,200
mov cx,1
mov dx,0080
int 13
int 3
(hit Enter again)
g=100
q
Eject the floppy - pop in the XP cd - and fresh install.