One of the best reasons I've heard for why people like
roller coasters--and
I can't recall where it's from--is that it allows for the rider to experience
the concrete fear of
death without the consequences.
I used to be very afraid of roller coasters, until at twelve years of
age a few friends literally dragged me onto one at Dorney Park while
we were on a trip from summer camp. I loved it, and immediately
saw what all the fuss was about.
I'd say most of the best roller coasters I've been on were at the Cedar
Point amusement park in Ohio. Definitely worth a trip there if
you're in the area. Other good spots include the various Six Flags
parks, the two Busch Gardens parks, and King's Dominion.