Installing baseboard over hardwood floors

http://www.VideoJoeKnows.com Installing baseboard over hardwood floors, is discussed in this short video segment. How tall should your baseboard be? Does it matter how tall the baseboard is, over the hardwood floors? How do I install the baseboard over a hardwood floor, without having to install that little trim piece at the bottom of the baseboard. Is there a way to hide the gaps under the baseboard, where it hits the hardwood flooring? Can I really make all these decisions myself & be comfortable with my decisions? http://www.VideoJoeKnows.com