Can't publish website? Help

Hi, I have built a couple of websites to send off to our server but each time I try it just crashes. I have tried creating a new one, I have tested my settings for the server and it says they are successful, I have downloaded Filezilla FTP and can connect to the server using the same settings??? Nothing is as straightforward as it seems but I have persevered only to find I can't load a site, is this a common problem? I think it just doesn't work. I have read the 'help' files, which aren't very, but have found that I can't load it to the server any other way, at least I don't think so.. has anyone out there got any suggestions as I'm beginning to think I have made a bad choice with these programs???!!!