Scott,

"I am using Port Zero(P0) mulitplex with HC245 as inputs, HC573 for outputs, and LCD Display 2x16. I am having capacitance problem on the bus. After I read the HC245, I clear the P0=0x00; However, Port 0 still remains high for a couple of us or ms seconds. I don't want to lose process power by waiting for the bus to settle."

Sounds like your '245 is trying to drive P0 when it's not supposed to. Check your direction and enable bits. Look at 'em on a 'scope. Check your code.

--a