A thing to remember, emails from ebay, banks, paypal etc or any asking to confirm your details, either delete or forward to the place where they are supposed to come from, most banks have departments that just deal with this sort of stuff, Also Richard W 3 things to say to you, backup, backup and backup
CD's cost pennies so there's no excuse not to backup regular it will save you a lot of heart ache, You could have reinstalled your network card drivers and downloaded MS new Windows Defender it's quite good and might have sorted you out