[bail]

I have the same problem. Seemed to happen for no reason. I think it
might be something to do with the context menu handlers. Check this
site for info about these.

http://windowsxp.mvps.org/slowrightclick.htm

I've not had chance to check these out yet. Maybe the dll that
controls this is knacked. I'll have a look and let you know if I have
any joy.

Good Luck!