"Having at last gotten Linux to run satisfactorily on my own PCs" - so you struggled and you want to foist it on others?
Leave them using Windows. Hell, be nice and buy them Windows 7!
Either that or get them a pretty looking distro (Ubuntu) and some unsupported hardware and have them build a driver from source, or better still recompile a kernel, then offer 'stick with this or go back to Windows'.
Tl:dr: Ubuntu... for two weeks until they get pissed off and hate you for it