iPhone Download Folder

So I downloaded a few files to my iPhone thinking I could access them later for transfer. They were drivers for that other OS. Does the iPhone store them indefinitely or what? How can I clear the downloads folder if I downloaded files that can't be associated with any app? Should I even worry about it? I also downloaded a couple home videos that I found aren't playing on the iPhone. These are consuming quite a few mbs i imagine. Kinda bugs me to have that space wasted if I can't access them to delete them. Suggestions?