Re: reformatting a pc?
You need to entirely reformat your hard drive, you could attempt to move files to a disc or an external hard drive.
Upon doing this get your windows install cd and pop it into the drive. You want to then boot the system from this disc and do a "custom" install if it is windows 7. You then right click your already used hard drive and tell it to reformat to NTFS for the file system and install windows fresh to it. You then need to reinstall all your programs.
It is not a quick fix, an average reformat for me takes roughly 2 hours including all my file system backups etc.
I wish you luck, but your better telling your mom and then reformatting the drive for her but letting her know that you've got all her files safe.
And if you got this from downloading "adult" content, i recommend not clicking a bunch of websites (i only say this as you seem awfully worried about your mom finding out, and I know my mom back in the day would have never cared unless it was something like that)
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