Virus Messing with Files

Hi, I recently got a virus on my computer and it really messed up my files. It says that the extension is correct (videos are still .mov, pictures are still .jpeg, etc.), but the icon is the one used for .mp3 files. When I try to open one, the computer attempts to open the file in Windows Media Player. I then get a pop up telling me that "Windows Media Player encountered a problem while playing the file." Any suggestions? Thanks in advance.