what anti virus do u use? get your computer scanned first thing make sure its all clear if its all good THEN change all your passwords. depending what u do on your computer it can be worth changing your ip but thats only if its a personal attack. paypal wise u should be fine as paypal should be able to spot it wasnt u that made the transaction but also get in contact with your bank aswell and let them no if u have a keylogger or a rat on your comp chances are they have all your bank details aswell.