box asks me for information of server and port to use a proxy when I try to download Flash

I am using the flash download page and removing the Mcafee check but when I press 'download' the download box comes up without any action and then another box comes up on top which says that in order to use a proxy I need to enter server and port information. I was not aware that I did want to use a proxy, I don't even know what on is. I have never had to do this before to download software. I uninstalled flash in a failed attempt to get iplayer to work by reinstalling it but now of course can't do either. I've printed off the 18 page troubleshooting guide from this site and will wade through it but I've been fiddling for three days now and have got nowhere so if anyone has any ideas they would be gratefully received. I can't find any mention of the word proxy on this site. thankyou in anticipation.