Is your service engine light on? Have you tried to pull any codes from the computer?
Did you change the whole distributor or just the cap and rotor?
I would first off check the battery's integrity - have it tested at your parts store. They can put a load test on it to make sure it's got plenty of cranking power. I would start there. I've had a few come in like that with the hard crank - it wound up being the starter being weak. If your cables are not tight or corroded that can cause that weak start as well.
Good luck, let us know what you find!