Here's something that has bothered me for awhile and I wondered if anyone had any ideas. This has been on multiple computers, but always at work and always on a dual monitor setup running Windows XP Professional. It's been multiple machines now that have done it, but both machines have had ample RAM and speed.
I'll be running with a lot of applications/windows open. For example, right now I have 20 items in my taskbar. Often I'll have multiple Outlook emails opened and multiple Windows Explorer (windows key + E) windows open, too. I have noticed a problem where at some point, after some amount of items being open(ed) and/or over a period of time, if I hit win+e to open a new explorer window it my system will start feeling unstable and slow, and the new explorer window that opens is graphically corrupted. Instead of the file/edit/view bar and the navigation bar, it will instead just have a blank gray bar with the Windows logo in the center (which is usually in the upper-right corner). Closing this new explorer and opening a new one won't fix it - usually it's only if I close out extra open windows to trim down how many things are open that I'm able to recover and open a new explorer window and have it work normal.
Is there a limit to the number of native explorer windows you can open in XP, or the number of windows/applications in general? Outlook and explorer.exe seem to be the worst offenders, closing out extra of those windows.