Re: How to beat the big dude.
If you're playing in an officiated game I like to try to get off a quick pull up jumper first to get him thinkin faster for the block. Then follow it up with a spin/drop step, followed by an up and under.
Basketball is much easier when you are moving at the pace you want to and your opponent is having to change directions and is thus thrown off.
If they're really really really really good and more athletic, get used to setting lots of picks and trying to get him to follow you out of the paint.