Okay, here's the deal.
I had been and still am unhappy with the frequent crashes that occur in the XP version of Movie Maker.
Back when Version 9 of Pinnacle Studio was the latest/greatest version, I paid real dollars for it, and found that it a) couldn't open the AVIs that I'd already captured using Movie Maker, and b) couldn't capture new video because the drive test failed. And no, I didn't get much help from Pinnacle support, as my system was using nVidia's RAID0+1 (which actually has phenomenal throughput), and they don't support hardware RAID. Phooey.
Fast forward to now. My office machine is still running XP because I have some Vista incompatibility issues on several important tools, especially Enterprise Manager for SQL 2000.
I've been working for several hours to capture, edit and publish videos for internal use, and Movie Maker keeps crashing on me. The main headache is the inability to save the final product as an AVI; it is fine for short chapters (5-6 min), but anything longer won't complete.
So I pull the source AVIs and the Movie Maker project over to my Vista laptop that I've brought into the office, and voila, the Vista version of Movie Maker doesn't even burp.
And rather than installing Nero to author a DVD based on the new AVIs I've generated, I used DVD Maker to do it. I'm a little disappointed that I was unable to give titles to the "chapters" I created, but the key thing is that it worked. Score another one for Vista.
Of course, I'm still hopeful that XP SP3 will include bugfixes for Movie Maker that will bring some stability and usability back to my XP boxes.