How do I protect an "original" title and logo for my blog?

The blog name itself, like film names and novel names, isn't protectible. But like the film and the novel, the contents, the entire work, is copyrightable, and you may want to copyright the contents - please see the Copyright Office circular linked below regarding online works.

And you can apply for registration for both the "word" trademark and/or the "design" (logo) trademark, and/or the design mark with the word(s) combined. An IP lawyer can help you decide how to proceed.

Finally. if you're starting your own website-based business, you should consult an IP/business lawyer about the proper website disclosures and disclaimers, formation of a business entity, liability insurance, etc. etc.

Disclaimer: Please note that this answer does not constitute legal advice, and should not be relied on, since each state has different laws, each situation is fact specific, and it is impossible to evaluate a legal problem without a comprehensive consultation and review of all the facts and documents at issue. This answer does not create an attorney-client relationship.

You will probably want to seek separate trademark registrations for the name and the logo. Work marks (of just the name) are typically preferable, but it is good measure to protect the logo as well. When registering the trademark you have to identify the goods and services that are being sold under the mark. You could potentially identify the commentary provided on your blog as the goods and services. However, you mentioned that you intend to sell other goods, which might also be used as the goods and services associated with the registrations. Just understand that trademark registrations do not offer blanket protection of the words/logo. The protection is only afforded if a competitor is using the words/logo in association with the same goods and services that you identify in your registration application.

To add to the other answers, which are very good, I suggest prioritizing trademark registration for the name of the blog as a separate WORD MARK (meaning you provide a simple plain text, design free, specimen of the domain name; that way should you use the domain name in conjunction with a different variety of stylized representations, the trademark registration would afford each of them a modicum of protection). I would prioritize the domain name also because it is the main gateway to your blog/services and will undoubtedly be used the most to identify your blog on a standalone basis and paired with your logo.

Secondly, one thing that you should understand is that you have trademark rights as soon as you use the trademark (in this case the domain name) in commerce. So, as I advise many clients, it might be best to see how the product and/or service fares commercially, before investing in the legal fees and costs associated with a trademark registration. This is because registration is a process whereby the federal government "recognizes" those rights and provides you certain legal tools and legitimacy to defend that trademark. In other words, registration does not bestow rights.

Disclaimer: This answer is for informational purposes only and does not constitute general or specific legal advice, nor create an attorney client relationship.