Windows 8 video apps? You mean the metro app? No. Unfortunately you can't.
You can use VLC Media Player, which is a desktop app.
http://www.videolan.org/vlc/index.html
It plays the majority of file types right out of the box, but you'll need codecs to play media like .mkv or .avi files. Download and install the combined community codec pack to play these, and all other media files with VLC. http://www.cccp-project.net/