its not necessary...
download
http://scream.civ.pl/hosts.zip unpack and put it to %windir%/system32/drivers/etc then restart windows...
if it not helps you out, download HijackThis! scan your system and post report here, or hit me up @ icq and send me it, i'll say you what you should delete to fix your system
also you can try CWSShredder, its a good prog too