[Homebuilt System] Operating System and User interface

I know some of these are done in a Linux Gui. I am trying to make a nice user interface for my kitchen PC. The user portal I am trying to get is something like

http://www.hp.com/united-states/ca [...] tml#/Main/

or

http://www.hp.com/united-states/ca [...] tsalt.html

Currently I have a Via C3 933, but I do not think it has enough horsepower. Even Ubuntu is fairly slow. I just ordered a ion board and prob will pick it up later this week, so that will give me more than enough horsepower for that.

So what is the best platform/OS/aftermarket addition to create something like this?

If you were looking at buying an off the shelf all-in-one for the kitchen you might have wanted to look at the Shuttle X50 Touchscreen with the 945 MB /Atom dual core CPU.
Shuttle SD50XB Black 15.6" All-in-one Barebone $410

Have you decided how big a touch screen monitor you need?
It looks like Linux support for touchscreen has come a long way in the past couple years: Linux gets native multitouch support [Video]
Linux native multitouch support

You did ask for ideas on a 'user portal' and linked in a touchscreen system.
And you did ask what was the best platform to create something like that.

You want to start over and be more clear about what it is you really want?

I guess I confused to many people. I though the title of this thread was pretty self explainaitory. I was asking what operating system could duplicated the user interface from the HP system. I know it is running on Vista and I know some Linux distro does similar but not exact.

When I say user interface, I was referring to smooth shifting icons. Sort of like on HTPC systems (meedio, mediaportal, MCE, etc) but without all the HTPC stuff.