To my knowledge, you DO NOT give over the rights to any video that you post on YouTube. Many cases you can find videos of movies and videos that are posted by other people and they may have comments that say “I DO NOT OWN THE RIGHTS TO THIS VIDEO”. It does not mean that YouTube does but it is just being posted for the pleasure of the general audience.
To answer the first part of the question, Mike Koenicks said “Focus on two things, answering peoples frequently asked questions & doing there SHOULD ask questions”. Just simply answer your audience’s questions. Always keep it short and make sure to maintain the same key word pattern. Make sure you use key words in the description section so that your video populates higher at the top when people are searching by using key words.