It comes down to personal preference. Both are free, and the newer versions have more security safeguards and more features so upgrades are recommended. You can also reserve a domain name at this site. B. Register with the search engines see next question for how to do this. You can also reverse search by telephone number.
Email is more difficult as there is no centralized database of email addresses.
The Web is not a technical phenomenon it is social one. The technology is merely the enabler. It can be compared to a large city with concert halls, museums, theaters and schools. However, in this city there are bad parts of town as well. In the same way parent would not drop their child off unescorted in the worst part of the city, you should protect them from the seamy side of the Internet with protection software.