Help with Chess

Probably the best site for players from the learner to intermediate levels would be: The ChessKid site (part of Chess.com).

For an introductory video: Learn to play chess

For puzzles: Test your chess skills

To play a computer (various levels) online: Play QWERTY

Some other sites:

Chess Rules

Chess Variants - The rules of chess

The Rules of Chess for Kids

FIDE handbook

Chess is fun

So you wanna learn how to play chess?

US Chess Federation - Let's Play Chess