Every font I try to download comes up as valid. Is there a file I may have deleted that is causing this? If so, which file should I try to download to get it to work?

Read the FAQ : http://www.dafont.com/faq.php
and follow the font installation method STEP BY STEP.

Thank you for the suggestion, but that doesn't help with the fact that when I download the fonts RIGHT off of here, it is an invalid file and there isn't anything inside of it. =\

Which unzipper doyou use?

I've used Win zip and the default one. What I think may be the problem is that I might have deleted a file that is necessary for font download usage. Although, I haven't the slightest which program I might have deleted...sigh