For either, it would depend on those contents and their media intensity (photos, videos, file lists, etc). You'd need to get an expansion or shield for the RPi or BB in order to do it.
You could also look at solutions that include touchscreens to start with. At Gumstix we have the Pepper Package, which is currently our only SBC, and includes a touchscreen display, AM3359 processor, 802.11b/g/n wi-fi, and gigabit ethernet. Based on the limited information you provided, it would probably fit the bill and give you flexibility for future projects.
