You have 2 Hard drives on your system C and D with Win XP Home how do you set up the boot menu to choose either one to boot from at startup?
If you're talking about a boot menu google bootmagic or go here: http://www.osloader.com
Assuming that the computer has IDE drives, the first thing to do is to install each operating system on each disk. Put one drive in the computer and install XP on it. When that's done, remove it, install the second drive and install XP on it. Remove it. On the first drive, set that drive as master, and set the second drive as slave. Install both drives in the computer. Start the computer and it will boot the first drive. In XP, open Windows Explorer, go to Tools -> Folder Options and click the view tab. Select the "Show hidden files and folders" button, click apply, then OK. Expand My Computer and select the "C" drive. Locate the "boot.ini" file, right click on it and select "Properties". If the read only box is checked, UNcheck it, click apply, OK. If it's already unchecked, leave it alone - click cancel. Double click on the boot.ini file to open it in Notepad. Under the [Operating Systems] heading, under the XP entry on a new line, add this entry:
multi(0)disk(1)rdsk(0)partition(1)WINDOWS="Microsoft Windows XP Home" /noexecute=opt in /fastdetect
Save and reboot. You should now have both systems listed in the choices menu. Select the second XP and cross your fingers. You should now have a dual-disk dual boot setup. If it fails, you can always boot back into the first XP as long as you don't change that entry in the boot.ini file.