hdmi?

[J9Darkwing]

Once again I turn here for some answers. . .
I have an hp w2207h widescreen monitor (22in 1680x1050) with hdmi input. I have 2 8800GT video cards with dvi outputs. Monday we're having cable tv installed and the DVR has an hdmi output and hi-def channels.
I'm currently using a dvi-analog converter plug on my vid card and going into the analog port of the monitor.
My plan was to buy a dvi-hdmi cable and a hdmi switch.
I'm going to run an hdmi cable from the cable box to the switch and run the dvi-hdmi converter cable from my vid card to the hdmi switch and then run the switch to my monitor.
Am I going through all of this for nothing? Will this monitor do HI-Def?
Here's a link to the monitor specs HP w2207h 22" Widescreen flat panel monitor specifications - HP Home & Home Office products
Will I be getting better video quality by doing this rather than using an analog cable and will this monitor work as a tv with the input from the cable box?
Thanks for your input.

 

[ricanflow]

If it couldint do hi-def, it wouldint have an hdmi input. It supports 720p just like mine. Itll work just fine, but you wont be able to view windows and cable at the same time. I know on mine i can since i have picture in picture, but it only wroks using component or vga in.

 

[J9Darkwing]

I realize that I won't be able to watch both. That's why I was buying a switch since I have only one hdmi input.
I know in this day and age this may sound silly but I have NEVER seen anything in hi-def. Is 720p good?