why does my wood look like this!

[monte]

How much sawdust is left in the cut? With too much set there is likely a lot left.

Well its funny you mention that!there is alot of sawdust left on the wood ???

[Brucer]

... the other thing, my roller guide does not extend close to the piece of 4x4 its still about 8 or 10 inchs away! :-\

That's a lot. Can you get it closer? 1 or 2 inches is where it should be. When I'm resawing dry stuff down to within an inch of the bed, I have to move the guide out to about 5" to clear my clamp. There's ususally some score marks on the wood right at that spot.

[EZ]

Make sure your wheels on your carrage are not siding back and forths. Even a 1/4 inch movement will cause a washboard look.
EZ

[barbender]

I would first make sure there is nothing on the bandwheels that could be making the blade jump up and down, and second,  make sure you're not putting a kink in your blades when you uncoil them.  I have kinked a few blades when they jumped off the band wheels on my homebrew mill, and they make a cut exactly like yours looks like.  It's the same effect as having one tooth over set like others have mentioned.  They still cut good and straight, but have a mark from every time the out of set tooth comes around.  If your feed rate is steady the mark will be evenly spaced down the length of the board if this is the problem.