Okay heres the deal *smacks self in head*. I've really f*cked up... My bro uninstalled steam for no apparent reason

, so i had to re install it. Sounds good eh? Maybe not! I downloaded my install from
Steam Powered ( Vavle's web page. ) and without noticing it saved into my directory D:/Program Files. Which is fine..... BUT my bro decided to be a weenus and re uninstall it. Okay, no problem i can always re install it. But when he uninstalled steam he deleted everything in my program files ( I have no backups ) and i had Norton anti virus..... It was saved under D:/program files as well..... well now I need to get rid of Norton because it blocked all my ports in its firewall after the semi crash.... now i have all these .dll's and i cant get rid of them. I'M SO CONFUSED HELLLLP ME!