Re the above link, after pressing R and then pressing 1, you'll be prompted for the Administrator password. If there is one, type it and enter. If not, just leave it blank and press Enter. You'll then get to the C:\WINDOWS> prompt.
When you use the bootcfg /rebuild command in XP's Recovery Console, you will be prompted to enter certain information.
When asked whether to add a certain installation of XP, say yes.
When asked for the load identifier, type:
Microsoft Windows XP Home
and press Enter (Home or Professional as the case may be).
When asked for the load option, type:
and press Enter.
When it's done, type exit and press Enter. Remove CD and let computer restart to see if it works.