Sorry if my English is not very good!
I did like this:
First you need to install the W2000 and after the WXP.
Put your CD of W2000 at your CD-R drive and run the installation! I recommend NTFS system files to W2000 and Wxp. (Follow all the steps recommended during this install!)
After, do the same thing to Wxp.
One boot menu file will be created when you restart your PC.
NOTE: Be careful with your data loss!
Good luck to you