?what wood, fiber or aluminum would you use?

I would like to lighten up my boat by changing my factory 3/4 ply wood with something light and strong, and then add new carpet.  What would you use and where can you by these things.  I live in beaver county.  Any advise would help.

Brother Angel,
       I would be veeerrryy careful before I would replace existing wood with any other substance except the same type of wood.  The wood in your boat is probably a structural member and was chosen, not only for it's strength but also for its' flex and shock dampening characteristics.  Also, does the wood need replacing?  If so check the structural members that the wood screws in to.  They may be bad also.  I'd use marine grade ply and find some other way to loose weight.  Like a smaller outboard.  Or just carry fewer people.  Don't forget whatever you put in will have to be compatable with everything else that will go on it.

Try changing the prop to SS.
If you have a tach make sure the RPM at wide open throttle is where it should be.
A different make in the same size and pitch will change performance.
Solid trim tabs on the transom might also help a little.

I have rebuilt a few boats myself & after sitting down & calculating the weights of wood verses aluminum the weight advantage of using aluminum was not worth the weight loss or the cost. One thing I did not check into was the marine grade plastics or what ever they are. After some experimenting I found 3/4" exterior plywood sealed on both sides & all edges worked the best & lasted for many many years. Hope this helps in your decision. Personally I would look at other areas to lighten your load, as stated earlier I would look at the prop, the RPM, how the motor is trimmed, & the weight distribution. Good luck      By the way I found 1/2" is not really strong enough depending on the distance between supports & the weight savings is not significant 

I wouldn't consider marine starboard an option for your floor. 1) It's heavy, 2) It's expensive, 3) It flexes alot, and 4) It's very smooth and slippery.
 
If having problems with your floor, I suggest you replace with plywood. If your current floor is waterlogged, it will be heavier.
 
But if your floor isn't water logged, I disagree with your approach to your boat not planing issue. I would not try to modify the OEM construction of the boat to lighten it. I would run a more powerful motor.

I had a 35 merc on it and it seemed to plane well.  Do you think upping the carb to 30 hp will be worth the expense?  Or would a ss prop help me more?  I don't have to change the floor I just thought it would be easy but I see from your(everyone's) advise that it may not be the issue. 
thanks guy's

I'd go with spoonchucker's advice. That being first try a different pitch prop and weight distribution. See what effect that has, then if your still not happy, try the bump up in hp and stainless.

I'm going to call evinrude and tracker to get there advise.  I'm also going to look into a rpm meter to help with prop selection.