A really great beginner class II and lake boat all in one is the Dagger Approach.
I ran the Upper C my first season in this boat and it is totally stable, never came close to flipping it in a rapid.
It also has a drop-down skeg for straight tracking on the lakes, I take mine fishing or just out for a power paddle on our local lake.
Awesome beginner boat, has a hatch for gear, tons of foot room and it is rollable because it has small knee/thigh rests and adjustable backband and footpegs.
Check one out, they're pretty hard to find used though...