If the LOGO is a work of authorship with creativity then it is a copyright property owned by someone or some entity. It others are using the LOGO...

What grounds would I expect to be sued on from the family of the original owner of a famous business who's TM has long expired?

While a Federal TM has expired there may still be common law rights and the product sold in a way that you cannot or fail to find. There is a...

Can I register for a name taken in the same class if it is in different business fields?

There certainly appears that the use proposed would not cause consumer confusion as to the provider of the blog in contrast to the provider of...

Is it possible to be awarded a patent even though someone else submitted a similar patent years ago but did not complete it?

It is possible that the earlier not completed examination of an improvement could be a basis for rejection of your "method". But your "method" may...

To what extent does legality of Terms of Services hold?

Terms Of Service comprise an agreement between the site providing a service and a person using the site. See cases re: terms of service for...

Yes. For example multiple photographs can be registered in one registration for one fee. See IP Attorney.

Yes, the mascot and the brand can have the same word or phrase or logo as trademarks. See IP Counsel.

Permission will be required to use celebrity images as cover photos on youTube videos. See IP Counsel.

What type of copyright and/or trademark do I need?

Have a trademark search to clear your proposed LOGO. For National Registration you need the bona fide intent to engage in commerce. Web pages are...

Yes. You negotiate or get someone who does this, an IP Attorney, to assist.