Dual boot options WinXP and Win7

Hello. I was wondering after you have already created a dual boot with WinXP and Win7, how do you avoid getting a second windows 7 boot option when installing another hard drive. The last time I replaced the hard drive, I now have 3 boot options: earlier WinXp boot, windows 7 and windows 7 again. Of course, one of them doesn't work since I replaced the hard drive. I guess also how to get rid of the old windows 7 boot option after installing your new hard drive, as well. thanks

Always unplug all other HD's during Clean Install Windows 7.

After install plug in the old drives, make sure you have all the files off of them and then run Diskpart Clean Command making doubly sure you are choosing the correct drive. This gets the drive cleaner than merely deleting the old OS and it's 100mb SysReserved partition in Disk Mgmt after if necessary marking it Inactive. Partition - Mark as Inactive - Windows 7 Forums.

If any unwanted boot menu items are still present after you know you've deleted all other OS partitions or wiped their drive, you can delete them in msconfig>Boot.