Can't view certain sites

[Computergen1]

On my desktop computer in which I have ll control of I cannot view any sites off of one persons server and any of the sites off the reseller of the servers. I have used different DNS IP's and still no success. I can visit sites like cf and other sites, this is really bothering me and I know its the computer not the ISP because the sites are viewable on my laptop. Note I cannot reformat and I have taken off my firewall and such and my computers aren't on a router.

PLEASE HELP!

ComputerGen