RB, WR and Flex help

[rhynorampage16]

I've got a big lineup decision to make as I've got many options in these spots. It is a standard Yahoo league. My league starts 2 RB, 2 WR, and 1 Flex. The flex option is RB/WR/TE. Please help me choose what to start, it is greatly appreciated.

RB: MJD, Steve Slaton, DMC, Donald Brown, Frank Gore (out)
WR: Calvin Johnson, Santana Moss, Steve Smith (NYG), Mike Sims-Walker, Pierre Garcon
TE: Jason Witten (starting in TE spot), John Carlson