There's no real way to control those two programs directly, so you will most likely have to use Girder (http://www.promixis.com/) in order to do so. You are lucky though, the new 4.0 version is so much easier to use than the older 3.3 version. As for the remote, at that point, it's pretty much up to you.

I am not sure of a remote that would allow you to do typing. Some PVR applications will place a keyboard on the screen for you, so you just use the arrow keys and enter keys to type, but you would probably have to consider a pocket PC or a Pronto to do this function, otherwise.

No, the ATI remote adds no functionality to your video card.