[Help] Choosing the right Hardware Dev Board for a Kiosk

Hi Guyz,

We are designing a kiosk which has a user interface.This kiosk will have an LCD(7 inch or 10 inch) and users would be able to do certain operations using the touch screen.
The UI will have 10 to 15 screens and each of the actions on a specific Screen will be a request/response to the central server.

With my limited knowledge of hardware,I was able to pull out some info after surfing the net for quite a while. As far as I understand there are varied options and I am unable to finalize on which is the best for our purpose.

1)At the foremost I should decide on the board and there are many options for a board like BeagleBone XM,FriendlyArm(was suggested by one guy),Arduino,RaspBeey Pi etc
2)Now is Arduino or Raspberry Pi suited for practical applications or are they mostly apt for educational or hobby projects ? As we have 10-15 screens with rich look ,will these micro controller based boards be fine ?
How abut BeagleBone black ?Would this help us ? I believe the BeagleBone XM is at the higher end in terms of cost and performance.
Are there are any other options other than the ones mentioned above and which are apt for our kiosk and which come at a decent cost.
3)I believe these boards mainly contain the ARM processors i.e Cortex Series or ARM 10 etc.
4)As we need to develop UI’s , which is the best framework or software for this purpose base don the board that we choose.
5)As the 4th point is dependent on the Operating System in few cases ,which is the preferred OS (Embedded Linux,Windows CE,Android,Ubuntu,For Arudino and Pi ?) ?
6)As android is popular how would it be suited as an OS in these boards.I believe the UI development will be easier in case of Android.
7)Are there any other factors that need to be accounted for ?

Thanks a lot for your time.