Q&A on Domain Name Registration?

I need help. I'm looking to register a domain name, and there's so many people doing it these days....can anyone give me some solid pointers here or guide me to an online resource to answer my questions? This would be for a business I'm interested in starting....it is a membership/networking/information driven business (NOT an MLM), basically I'd provide some info for free but offer a membership with special additional perks and $ saving opportunities at venues my members would be highly interested in.

I'm looking to have my questions answered prior to committing to any one provider...everyone's promising help, but I'm not sure what I really need. Anyone who's traveled this path before me, I'd appreciate any info/advice you have.