I used to have an 8 foot Sportyak dinghy that carried on the hardtop of
my 30 ft. Chris and it had a sail kit. I used to take out on Anchor
Bay (in good weather only) and it did OK. Not the greatest lines for
a sail boat, but was fun . If you're only planning on going on a
small lake, I don't see any problem with a 13 footer. It would be fun
to learn with and you may decide to move up into something bigger. The
poster telling you to wear PFDs has a good point, a boat like that can
tip over pretty easily. We used to have a Wayfarer Class regatta on
LK. St. Clair and these were 16 ft. boats. They handled the St. Clair
chop pretty well.