I am guessing that you mean that there are no Desk Top Icons, or you can not run any programs that you are either opening or trying to open ?
If you are completely in the dark, and you can not get programs running,
You might try getting into the safe mode and selecting last good configuration from the black background page before clicking directly into the safe mode, then click on last good configuration. OR, . .
you might consider looking into the System Restore,
Start>All Programs>Accessories>System Tools>System Restore
Here you can restore to the last restore date, which you should consider if your PC was in good shape on that date.
Edited by Jove, 17 October 2009 - 02:28 PM.