I'd get a hdmi switcher, i think they are under 50$ on monoprice. Although before you order one you should ensure that hooking your computer up to the hdmi port works (temp unplug the DVR).

If you’re using a laptop] on a daily basis, you’ll know how tiring it can get to stare at a 13-inch screen for hours on end. This is why it’s great that most modern computers can be connected to a TV.

I finally decided to drag my old PC out and see if I could use it as a poor mans HTPC. I don't have the optimal cables on hand hook it up, but I was able to get it to work halfway decent last night.