Parallels install after Boot Camp

I suggest you download the Boot Camp software from Apple and read the documentation carefully. Visit the Parallels' site where you can also download a copy of the documentation and read it carefully. Both docs explain how to install the software. The Parallels' doc will explain how to use a Boot Camp installation for a VM. However, if you use Boot Camp there's no need for Parallels (and vice-versa.) Having both is a duplication of effort that's really not necessary.

If you need information or support for Parallels then visit their forum: http://forum.parallels.com/. The Apple Discussions does not provide support for Parallels.

For Boot Camp support visit the Boot Camp forum which is a separate forum in the Apple Discussions.



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I'm quite familiar with Boot Camp and Parallels. Parallels can use the Boot Camp volume for a VM. You will find this on page 97 of the Parallels' manual.

If you are interested in VM then you should also take a look at VMWare's VM Fusion (now in beta.)

I installed boot camp first, well before I bought parallels and then I used the boot camp partition for a virtual machine in parallels--it did not ask me to validate my XP installation again.

However, I have heard that the next time I boot using boot camp I may have to validate my XP copy. But I have no reason to boot into boot camp since Parallels runs XP amazingly well--even for some of the pretty intensive software I use it is faster than a stand alone Dell XP machine (and that's running OSX and XP at the same time!).

Cheers

If you are interested in VM then you should also take
a look at VMWare's VM
Fusion (now in beta.)

FYI, this link goes to a "Page Not Found" message. Here's the VMware Fusion page:

http://www.vmware.com/products/beta/fusion/

I have a new Macbook Pro on the way and am trying to figure out the best way to install Boot Camp and Parallels and only activate my copy of Windows XP one time

I'm afraid they're no way around having to activate two times. Due the the differing environments XP/Vista will think they it's actually two computers.

Do I install Boot Camp first?

If you want to use the same partition/installation of Windows, that is from your Boot Camp partition, to run Windows then install it from Boot Camp first. At a minimum it'll be quicker.