Your space, judging by that photo looks narrower. In a space like this I would consider placing the dining table and chairs in that space by the window and the living room space where you have the dining table. It seems like it'll give you a little more room to stretch your legs.

I like the last layout best. It creates separate eating and conversation areas and makes the space cozy instead of awkward. (with the sofas sort of facing the window. I don't think you'll want to be climbing over sofas to serve dinner. But I also like the sofas facing one another. Still a cozy area without putting your back to the room.

First of all congrats on the new house! Wish you lots of joy and happiness while living in it!

Here is my version of layout of the furniture:
http://uploadpic.org/v.php?img=gOV50zDm5m

In brief,
*a chaise longue next to the window ,
*a small coffee table (which you may easilly move to the small part of the wall at the end of the chaise longue under the window) ,
*a footstool (high as the chaise longue), which you may use as additional extention of the sofa and thus having two places on the sofa for relaxing,
*TV cabinet
Add some nice curtains, plants, wall art and you're done :)