Sounds like an application is hanging, try closing all your applications, and quitting any programs in the notification area (lower right corner). Also, right click on your start bar and going to task manager, perhaps you can see what program might be hanging (e.g. iexplore.exe, WINWORD.exe, OUTLOOK.exe, etc.) Don't aimlessly end stuff, but you can also post a screenshot if you're unsure.
If you can't fix it with Windows System Restore, then you'll have to trouble-shoot.
Windows System Restore can save you hours of needless trouble-shooting and at no cost. if you have 8 computers to fix in your desktop support job, this would be a no-brainer as it would fix it 99 percent of the time saving hours of your time as a tech, and hours of the user's work time.