Desktop/screensaver prefs, hang, crash

Question

I have two monitors.
I installed 10.6.4, earlier, and a number of things began to go wrong, including the above: One of my monitors lost its desktop picture. When I tried to fix it with desktop/screensaver prefs, the system prefs basically crashed.
No biggie, but it seemed wise to me to wait, as I have in the past, for the bugs to be squeezed out of 10.6.4. I downloaded and installed 10.6.3 again, and most of the problems that came with 10.6.4 were gone. But not this one. I can change my desktop picture on my MAIN screen by choosing a picture in iphoto and selecting it for the desktop. The other screen can't be changed. The desktop/screensaver preference makes system preferences crash. I can live with this, of course, but if anybody can suggest a solution, I'd be grateful.

Answer 1

Solved it.
Thanks to some other queries about this same thing,
I just took it farther than anything suggested: As follows. Went to library, preferences, and, from both regular prefs and "by host" prefs, I trashed:
/Users/xxxx/Desktop/com.apple.screensaver..Mac.001b639db71a.plist
/Users/xxxx/Desktop/com.apple.screensaver.0017f2f382a6.plist
/Users/xxxx/Desktop/com.apple.screensaver.slideshow.0017f2f382a6.plist
/Users/xxxxr/Desktop/com.apple.preference.displays.0017f2f382a6.plist
/Users/xxxxr/Desktop/com.apple.PrefPane.Network.0017f2f382a6.plist
/Users/xxxxx/Desktop/com.apple.screensaver.slideshow.001b639db71a.plist
/Users/xxxxx/Desktop/com.apple.systempreferences.001b639db71a.plist
/Users/xxxxxx/Desktop/com.apple.preference.displays.001b639db71a.plist
/Users/xxxr/Desktop/com.apple.screensaver.001b639db71a.plist
/Users/xxxxr/Desktop/com.apple.desktop.plist
/Users/xxx/Desktop/com.apple.systempreferences.plist
/Users/xxx/Desktop/com.apple.desktopscreensaver.rsspictures.plist