I set the refresh rate at 60?

When i go on this site i see something weird things, I guess it's called the flicker because when i scroll if flashes.. when i visit other sites, it doesnt do that.. how do I get my original setting.. because i tried to change the 60 but i can't it wont show the other optionsI set the refresh rate at 60?
It is unlikely that the refresh rate for your monitor is only affecting one site... if you cant change your refresh rate, then perhaps your monitor only supports 60 hz, otherwise maybe it will allow you to change the refresh rate if you change your screen resolution first, try starting at 1024X768