system restore

ok heres the thing i wanted my sims 2 game back bcuz i uninstalled it and so i did a system restore to get it back and now everything is screwed up on my computer my norton anti-virus is gone and it screwed everything on my internet up my yahoo will not work correctly because when i type something to someone it shows in the box but when i enter it i cant see what i type or what they say to me and my webpages are messing up and i cant undo my restore because when i open restore it just stays blank i probably F**** my computer more by doing restore so im downloading avg virus protection for now bcuz i cant just leave my computer without anything to help and when i try and go into yahoo games or something it wont load and i cant delete my e-mail just receive things and i cant download anything if anyone has any help at all for me please tell me i really really need it