I did a quick search and there doesn't seem to be any pure trainers designed for a .91 4-stroke. In my opinon best bet would be a Sig Cadet Senior its supposed to take a smaller motor than your .91 but at 80" it is a big bird. You could always use a three bladed prop, which would let the prop clear the ground and give the oversized motor a little less power. If this is to be your very first plane, I would probabily pick the Cadet Sr. ARF, it's a little pricey but shouldn't take up your whole wad. Sig's ARF's are very nice and the ARF has many improvements over the kit ( a cowl, two piece wing and aelrions.)

If you already know how to fly and a looking for a plane to get you into scale modeling then your choices are legion. There are many kits and arfs of big tailorcrafts, Piper Cubs, Citabria's, Super Decathlon's that all make easy flying planes but don't quite qualify as a trainer.