MS: Whether to enable new site for new register

Could someone please provide me with an opinion on my site signup configuration? To simplify the signup procedure, thus reducing confusion, should I disable the option for a new register to create their own site/blog during their signup?

It has dawned on me that perhaps I should simplify the process. I think once inside and they start looking around, they will notice the "Create a Site" button under the Member Sites directory.

Perhaps I'm misunderstanding the settings and they have to be offered the opportunity to create a new site while they are signing up for an account.