Although it doesn't appear to at first, Fraps will capture your games in Windows 8.  Current Fraps (ver 3.5.9) doesn't capture your Desktop or Start screens.  Not to despair. It will capture many applications when they are running, especially your Games.

You can use the same settings, except the Aero Monitoring and it will capture your games in the directory you set.  Usually your C:\Fraps\Videos directory.