Hi, just continuing the first posting, is your computer/PC/Laptop/Notebook run slowly?. Here is another tip for you. Read it.
So your PC is acting wonky and you need to reinstall Windows. Starting from scratch can take hours. The faster solution is to back up your data (as described in the item above) and then use the recovery tool that accompanied your PC. The tool usually comes either as a bundled CD or DVD or as a hidden partition that you can access at boot time. Consult your computer's documentation to see which setup applies.
Recovery tools usually work by overwriting the data on your hard drive with a fresh image of the factory-default software. Windows will be back up and running quickly, but it won't have the programs you installed on it, or your settings. Restore your personal files from the backup you made before starting this process, and then reinstall any applications you need.