Sounds like your system got slammed with malware/virus. If you boot your computer and keep hitting f8 can you get to Safe Mode to run malwarebytes or your antivirus. Personally to me sounds like you will need to wipe the drive and start clean, but as this is XP might not be able to as support has stopped for XP and companies aren't making drivers / etc. for it. If wiping, reinstalling all software (having the keys, etc. for them) and all that is a big hassle and probably not be back to where you want to be, you might just fork over the $249 at Walmart and just get a new PC, some older low end systems are even being sold for $149 on Walmart.com. Someone linked me here to a i5 nice system on Walmart for lik $450.