I just input a new upload script on my site. Works a wonder, all i want to do now is limit what files they can select to upload. I know you can allow them to upload only specific files but thats not what i mean. When the dialog opens to select the file off their machine i want it so they can only see .torrent files, rather than all files. I did a quick search on the web but was not sure what to search for and couldent get nothing out of what i did search for.

There is a standard for an accept attribute, but it is not widely supported in browsers. I am afraid you are trapped in front-end support dark zone on this one. I think only opera and chrome browsers support his. And even if they are supported, the only standard mime type for a torrent file there is are bittorrent files.

So you can try using but it is not guaranteed it will work in all the browsers.
You can try use javascript, to verified only. I don't think it would let the dialog to only show .torrent files.

There are also some flash laternatives, like uploadify

But there is no sane option in this problem.

P.S. I think this thread fits better under TalkPHP > Misc. Support & Development » Javascript, AJAX, E4X

I had worked on something similar but I never found a solution. Not sure there is one.