|Ah, the HTPC: my favourite kind of computer. :)|
Skip the UPS...a $15 surge protector will provide enough protection. I know I'll get "flamed" for that comment, but I've never used a UPS and still don't regret it.
Using the money saved, buy a cheaper motherboard without integrated graphics + a videocard. You'll need more than the integrated 9300 chipset to play games. There are some Asus P45 boards (open box) over at newegg for $69.99. Here's an example.
Then add a GeForce 9600GT or Radeon HD 4670:
Asus GeForce 9600GT (open box) - $78.75
Asus Radeon HD 4670 - $79.99
And what's an HTPC without high definition? Here's some other stuff you may wanna look at:
HDTV tuner with Windows Media Center remote
I personally don't like HDTV tuners--they're just too limited. Don't even have one in my HTPC anymore. Now, I have my satellite box connected to the receiver and just switch the input source whenever the urge to watch TV strikes. However, a lot of HTPC owners seem to like 'em, which is why I gave you the link above.
This guy also burns DVDs, so if you decide to purchase it, you can obviously save some money by not purchasing the LG burner listed in your original post.
Note that if you plan to watch all of your movies on that 19" LCD, purchasing a Blu-Ray drive may not be the best idea. Plain ol' DVD still looks fine on displays smaller than 24".
Samsung 1080p panel
2 HDMI, 2 Component, 1 VGA
120" 16:9 screen
Connected to: HTPC w/ BD, satellite receiver, XB360.