I have to agree with Sander. Choose a good quality exterior latex house paint, prep the surface like you would anything else by removing anything that is not sticking well, lightly sand and paint it. I don't think you want to use an oil based since putting that over latex is a bad idea if that is what is on there now. Latex is fine going over either latex or oil. Since the interior paid is not subjected to direct weather a good quality house paint, which is subjected to weather, will work just fine.
You will regret the things you did not do, more than the things you did.
Get out there!
Saco Bay, Maine
2001 Beneteau Oceanis 361