1. Download HyperCam
2. Open it up and click select window and select the toribash window.
3. Press enter in Toribash (to write a command) and write /opt hud 0
4. Press esc two times too take the game and toribooster boxes away
5. open your replay
6. record in hypercam
7. Edit in movie maker
i personally use Camtasia Studio...
but I'm not sure if it uses up more RAM than for example Fraps, because Fraps is especially for recording from Games...