By changing the boot device startup sequence, I can boot from my HDD that has runs XP or from my HDD that runs Vista.  I now have SP installed on the XP HDD.  Can I do a second install of SP on the HDD that runs Vista?

 If not, I presume can I back up the Vista HDD to my backup HD from SP running on my XP HDD.  Also, I presume that if I have to restore Vista, I could start up under XP and run SP to restore Vista (and vice versa).

 I'm especially paranoid with Vista, as I have had a couple of false starts.  I recovered fairly easily, because I also periodically create a complete backup image of Vista.  This is a pain, because I have to (1) remove the XP HDD,  (2) install the Vista backup HDD, (3) back up my current Vista HDD and (4) reinstall my XP HDD.  I expect SP to be a much better way to backup.  In any event, I will continue to periodically make backup images of both my XP HDD and Vista HDD.

Thanks for any feed back.

 

You can't install and activate SP on Vista unless you buy a second license because all licensing info is within the XP machine. Any SP in Vista will not know about the licensing info in XP. Backup of the Vista volume in XP should be no problem.