Question about YouTube intro

I'm making an intro for a YouTube channel I'm planning to start. I don't want to end up in some copyright turmoil regarding my intro.

It uses royalty free music and I was planning on using parts of some game trailers that I would cover on the channel. Is this something that will get flagged for copyright? Baring in mind that I will be using the same games as a compilation in the videos?

I'm not sure if this is the right place to ask this question though.

Do I need to try and get in touch with the developers etc?