I will be in Krabi on Nov. 23rd for 3 nights and want to see as much as I can in 2 1/2 days. Maybe 2, one day island tours and 1/2 day, if possible, to tour Emerald Pool, Hot Springs, water falls. Would I need a tour guide or hire a driver for the 1/2 day tour? I think I would need 2 separate day tours to go to Phi Phi Ley and Phang Nga Islands.

I will be staying at Ao Nang Villa Resort. Any suggestions would be appreciated, even names of guides and island tours.

wassala

Yes, the speedboat tours for Phi Phi Islands, 4-Islands, and Hong Islands excursions depart from Ao Nang around 9AM and return at various times to a port west of Ao Nang and Napporat Beach subject to which tour. This should include a free transfer back to Ao Nang.
But you could also do a trip to Phra Nang and West Railay on your own via longtail transfers from Ao Nang's longtail kiosks. If you go to West Railay by longtail, then you can take the connecting paths to East Railay and get to Phra Nang via a pathway, reversing and returning to West Railay for the transfer back to Ao Nang.
But the 4 islands tour does include a stop at Phra Nang as well for a short period and no time to hike to the emerald pool.

You definitely need transport to get to the Emerald Pool and hot waterfall. There are day trips available from your hotel, but they are all day affairs that might take in sights you don't want to see, so a car with driver is a reasonable alternative, and possibly cost effective if there's more than one of you.

We self drove around Krabi to the hot-stream and emerald pool.
It is one of the easiest places in Thailand to drive and it is extremly well sign posted. Others will disagree with this but I believe this is the best way to explore this region.

You certainly dont need a guide or a tour. If you are not confident enough to go it alone, a driver and car will suffice.

Dont worry about pre-organising this or getting a recommendation, you will find someone without any trouble...in fact, they will find you.