For both you and the OP who are having Explorer problems - they are likely due to an incompatible shell extension, or two or more extensions fighting.
As a quick fix, you can select “Launch folder windows in a separate process” which will at least fix the problem of the whole system freaking out (tray icons and desktop icons going away) when the Explorer process crashes. In Windows 7, this is in Start / Control Panel / Folder Options / View (tab).
For actually correcting the problem, you could use something like ShellExView to see what extensions are loaded. My system has 175, of which almost all are from Microsoft. Look at the others and see if disabling some or all of them fixes the problem.