The ONLY shorts that ever worked for me were Pearl Izumi compression shorts with a 6" inseam AND leg-grippers. Eventually they ditched the grippers, which makes them ride up like every other gripperless running short.

I'm back to running exclusively in running skirts. A quick roll of Sport Shield on my inner thighs and I'm good to go. No unflattering or irritating fabric between my crotch, since the ones I wear (generally SkirtSports, though I've worn RunningSkirts.com's skirts, too--their sizing is just too all over the place, so I don't buy them anymore) have liner briefs, not compression shorts.