Help with folders that don't allow deletion

Hey! so I downloaded a file which asked for admin password to install. Foolishly, I thought I could sneak past security and find the files by viewing contents. I moved some folders onto my desktop, and now I can't remove them without admin passwords, for some reason. I've tried changing names, places, content, nothing works. these damn folders are still here. any way to get them out of here without admin password, or am I screwed?