connecting PC to my HDTV with HDMI

OK - I'm confused and apparently a dork for not understanding something "everyone" seems to get - except me...

I have a descent PC, good ram, nice system, running Vista. I also have a Sony Bravia HDTV very close to my PC. I want to "connect" my PC to my tv so I can download movies to my PC, but watch them in 1080i format on my TV. The issue seems easy enough, but I'm missing it...

The TV has plenty of inputs, but I think I should use the HDMI ability. I dunno..

1) If I download a dvd like "Dark Knight", is there a "format" I select?
2) I then would need to make a DVD of the movie so not to pack my hard drive (its only 160GB). What drive do I buy? any DVDRW?
3) THEN when I want to play it on my TV, how do I "upconvert" the movie to 1080i from my PC?
4) and finally - (no sarcastic comments here...) where do I put the HDMI cable in my PC?

Many young and impatient sales reps at BestBuy and Frys Electronics obviously know this answer but no one seems willing to explain how this works. I have to imagine Toms Hardware (or SOMEBODY) already has an article on this, I just cant seem to find it.

Sorry for asking such a dumb question, but can someone point me to an article or thread?

I really appreciate it...

Solution is given but for a laptop: http://forums.techarena.in/mediacenter/901511.htm

See this tip and video :How to connect your PC to your HDTV
How to connect your PC to your HD TV
Hope this help you.

Your PC may not support dual displays.
Disconnect your VGA display.
Power up the TV
Connect PC to TV via DVI to HDMI.
Turn on TV
REBOOT PC. Do you see the boot screen on the TV? Yes, that's a good sign. No? Your PC's DVI may be analog only, which is not supported by TVs.