Help! I can't uninstall Vista SP2

Earlier this month I installed Vista SP2 and blogged about it in Vista SP2: Less than meets the eye.  After several days decided it was time to uninstall it. But now, to my chagrin, I can find no way to roll my system back to the previous state of Vista. Can anyone help? The first one to solve the problem will get a free copy of my book, Windows Vista in a Nutshell.

When I installed SP2, I first created a Restore Point, figuring that I'd be able to roll back to that Restore Point when I was done reviewing SP2. Several days later, though, I was surprised to find that the Restore Point was gone. In addition, the SP2 installation didn't create a Restore Point of its own, or if it did, that had gone missing as well.

No problem, I figured. I'll just go to Windows Update, find the SP2 update there, and then roll it back from there. But Windows Update didn't list an update, which surprised me. I had installed SP2 via a standalone installer, rather than via Windows Updates, so perhaps that's why it wasn't showing up.

So here I am, with Vista SP2 on my system and no apparent way to get rid of it. When the next version of SP2 comes out, I believe that it won't install unless the previous beta is uninstalled --- but I don't seem to have any way to do that.

Any advice on how to uninstall SP2? If so, let me know, below.

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