I'll help however I can; I'm pretty good at explaining complex techie stuff to non-geeks... give me a job

I think the booth should have tablets:

• with a nicely stocked menu / home screen, for fooling around
• running Numpty Physics
• showing a full-screen movie (non-interactive)
• running Maemo Mapper (w/GPS)
• running Canola with a variety of pre-loaded media
• video conferencing between two tablets
• running a slide show in Quiver (or interactive browsing of pics)

perhaps, also:

• VNC to a Windows or Mac laptop
• running a game playable with a USB joystick / wii controller
• hooked up to a monitor / TV via USB2VGA, with a slideshow
• running a word processor (KOffice? AbiWord? OpenOffice?) with the ability to print, maybe with a nice BT keyboard
• running an alternate WM (kde, icewm, enlightenment, xfce4, etc)

Anyway, just some ideas to think about...