We have driven to Krabi from Phuket many times over the last 5 years and its a lovely drive of about 180 kilometers. 
It normally takes us quite a few hours as we stop off at various places along the way.  The roads are good and well signposted.

Phang Nga town is in a valley among huge rocky limestone mountains covered with greenery and the entrance to town is very pretty with parks and gardens.
Its not a huge town there’s fresh food markets, lots of little restaurants, Buddhist monasteries, a market selling clothes etc plus all the normal little shop houses you would see in any town.
There are also many caves and waterfalls around Phang Nga and the area is still primarily rubber plantations and forests.

From Phang Nga town we decided to go back a bit to the turnoff to Phang Nga Pier, soon we are driving past mangroves, then someone runs out onto the road and stops us, my god, he is trying to sell us a tour to James Bond Island (rock) a few meters down the road and another one runs out and stops us, same thing.
After traveling about 50 meters and being stopped (or we would have run them over) about 5 times the same tour has gone down to 400baht for the both of us!!

Gary has had enough, he has that look in his eyes that says Road Kill coming up, so we turn around and head back to the main road.  I’m sure if we had kept going to the end of the road to the pier we could have gone to James Bond Island (rock) nearly for free with a set of steak knives thrown in.

Off we go again, we are on the Krabi road, it’s a great scenic drive through lots of little villages, and there are lots of stalls set up on the road selling food.

One little village called Ban Klang had numerous stalls near the road cooking chickens on a rotisserie and each stall had a cord with a light bulb, some of the lights were on, we figured this was to let passing traffic know that the chickens were cooked and ready to buy.

The beaches around Krabi are so pretty and quiet, no crowds, no jet skis, parasails or sun lounges on the beaches, no tailors or tuk tuks annoying you - heaven.

I do not have much info on shopping or nightlife on these pages.  Everything is available here, same as Phuket but on a much smaller scale.
Massages were cheap here, 200baht per hour, food and drinks were also good prices.
It’s a great place for families (in the low season).

Its fantastic driving yourself to different places, each trip we average just over 5000 kilometers. 
We have never had any problems along the way and would have to say that the best thing we have ever done is hire that 4x4!