Disabling Picasa2 Media Detector didn't help. Roots Magic still shuts down.
I've now enabled Google Desktop search but told it not to search the Roots Magic folder. I'll let you all know how that works.
Don't take this the wrong way but I'm glad to see that other people are experiencing the same problem I had. I had thought that it was just RootsMagic clashing with Vista; strange that it is also happening with XP.
Mine kept going blank and/or closing too. I finally had them send me RootsMagic on a CD (I had downloaded it from their website), reinistalled it from the CD, and so far it's performed flawlessly.