I'd appreciate it if someone could enlighten me as to the differences between a regular vs. a "racing" flywheel.
The name. Well, like Scott says, something that is SFI rated and maybe lighter then a stock wheel and NOT cast iron.
A real racing wheel may also have replaceable steel inserts so that if the inserts warp you just drill out the rivets and replace the insert. This is typically used on aluminum flywheels but I don't see why not a steel wheel? Most race cars use alum wheels as it has less weight to accelerate...hence a faster ET.