I am 5'1", 110 lbs and ride a 143 Ride Rapture. This is a full rocker..My last board was a 139cm Rossignol camber board. I cant tell the difference of the length since it is so slight but I can turn alot better.
Most wouldn't agree with going to a full rocker..A hybrid board would prob be best.
Check out Eriksbikeshop.com for some killer deals..I picked up the Ride board for $74.95 there on clearance 2012 model. For that price, I could prob sell it for more than i bought it for.