I'm looking for a media center for a van installation. I've looked at the many out there. I use LinuxMCE for my home, and XBMC on my xbox. The problem is they don't scale to a 7" touchscreen. It's to be controlled by kids. I'm not picky about distro as I run many depending on the need.

I have a freeBSD minibox router at the office with 4x nic for load balancing internet connections so I was looking to get one of these.
http://www.mini-box.com/VoomPC-2-Car...8&category=101

Really it's just for playing handbrake rips of our DVD collection so just need a decent GUI for cover art selection from the HDD. Would also be nice if I could manage without a keyboard (delete or copy from USB/Samba)

Have you tried Slax? Is a very nice distro were you build your distro with the packages you need, so you can tailor it to your needs.