I've been on a fair few roller coasters in my day and a long time ago I figured out the 3 different roller coaster personalities.
Personality 1: The silent ones- they're the kind of people who either don't find the ride exciting or just aren't a very vocal type of people.
personality 2: the screamers-yes we all are more than familiar with these ones. They are the ones who scream at the top of their lungs with fear. We've all been next to or near one, and have suffered the ringing ears afterward.
personality 3: the yellers- they are the ones who genuinely enjoy the ride and express their feelings in a less ear splitting way than the screamers. They're the ones with their hands high in the air during a 70 foot drops and corkscrew flips.
technically there's a personality 4. They are the few and far between people that make other strange noises. Some laugh and others swear, either way they're kind of fun to be next to.
while we're on the subject I'm going to say which rides are my favorites. In my opinion the faster and more stomach dropping the better. Out of all the places I've been to (Six Flags, Disney, etc.) my two favorite coasters are The Kracken in Sea World Orlando and Dueling Dragons in Univeral Studios Florida. Both are absolutely amazing, though dueling dragons has two seperate coasters, ice and fire, and I've only been on fire. But dragons gets bonus points for being really cool and having two seperate tracks and coasters intertwine.