For a newbie, those are both pretty large plugs. I would consider getting a smaller toy for your first plug. You might look into the small (or at least the medium) Plug of Lust, the FunFactory Bootie, or the LELO Bob.
Of the two, I would definitely go for the Ryder, but with a diameter of 1 1/2 inches, it might not be the easiest beginner toy. If you've used toys anally before you'd probably love it. If you are looking for a more "beginner" toy, with a smaller diameter, I've heard great things about the Bootie.