Can't connect to various websites

[patpat81]

About a week ago. I have been unable to connect to a couple of sites. When using Firefox I get the error "the connection was refused when attempting to contact blahblah.com"
When I try the same site with IE, I get a 404 error.
The same goes for my other computer.
The only way I can connect to these sites is through my AOL browser...
Any help? Also please explain like you would to a layman. I don't know what things like Proxy mean.

Thanks fo your help

[kaled]

The fault may lie with your ISP. If possible, try a dialup connection. If you can access the sites via the dialup, call or email your ISP for support. Unfortunately, they may instruct to make proxy settings.

Kaled.