Newbie attempts to media'ify lounge - building on 42LG7000

[cranny]

Hi all,

I've been doing a fair bit of research, especially around this sweet forum, and I've decided to give this whole DIY pimping thing a try in my lounge/top floor flat! Whilst quality is important to me it's not paramount. I'm looking for a setup that looks good and performs.

So far I've got:
LG 42" 7000 Series
xBox
Broadband Virgin Media (through BNC connector in a modem then onto wifi router)
Dwell Wall Hung TV Unit

22042009293 on Flickr - Photo Sharing!
Excuse the mess as life clashes with DIY...

With a view to get:
An LG Theater System - eg. LG HT503TH
--can SimpLink it with the TV and it looks good, but I'm open to input
Media Storage (Media PC to store media and quick net access/stream music via Spotify --or a fancy xbox OS?)
Sky+ (not immediately but soon)


I need some advice on bringing it together.

The wall unit already weighs alot, it's heavy wood and the TV isn't small. There is a glass shelf to go on it but I don't want to put equipment on it. I was planning getting shelves to sit in the corner of the room to hold the extra technology.

I want to put all the cables between the tv and the corner in the wall but I'm not sure what ones I need to do this with (including future proofing to a degree).

Here is my plan so far...please advise me though...I'm new to this!
Behind skirting board and up the wall:
4x HDMI cables (can be split into component if necessary once out of the wall?)
1x Optical Digital Audio
2x RJ45 (might as well, cheap as chips)
1x COAX (Aerial for the TV)
1x RCA(/Scart)
1x VGA/RGB
1x Audio Jack
3x Speaker cables (two front and centre speaker)
What else should make the journey?

1x 240V (tapped from the existing plug in the corner or fire place fuse?)
Will the load on that plug be ok handling all this? Or should I tap it from the plug on the other side of the TV

Custom made faceplates - so far most suitable is in Australia
1x Big one for the corner with the above ports AND surround sound
1x Above (but only one centre speaker) to go directly behind the TV unit
5x Speaker ports for around the room from this guy


And now onto the connections...
Theatre System, XBox (and Sky+) to the TV. Then feed the Optical Out from the TV back into the Theatre System.

Will I loose Surround Sound functionality from the Xbox and Sky+ doing this??

The HT953TV system has an HDMI IN - and I read about people running things through and HDMI swith with everything into it - but it's twice the price of this system and from a sound quality perspective I don't think I will appreciate the difference - I'm sure even the HT503TH will impress me! But if it's the only way I can do it I might need to reconsider...


Not sure what else I need to tell you...post any questions and I will do my best to answer. Your input is greatly appreciated!!

Thanks
Iain