We stayed in Litchfield the last couple of golf trips. We like the Hanser house for a good quality dinner. Quigley's is a good bar/restaurant. We usually went to Murrells inlet one night. You could also head to the PIT if you go to Pawley's. We don't do pizza so i am not sure what is good.

If you are in Pawleys, Franks (upscale/reservations) + Gios (Italian) are good.  
I also thought Hanser House was good.   
Drunkin Jacks in Murrells Inlet. 
 
I don't stay south, so eating dinner south is only after a PM round there.  

I would add The Claw House in Murrell's Inlet, good food reasonably priced, a second vote for Quigley's. In Garden City on Hwy. 17 try Texas Roadhouse, again decent prices, downside always busy. 

Captain John's is very good.  Moe's Original BBQ is also near you.  I have lunch there once in a while.  It's always been solid.  Applewood Pancake House for breakfast/lunch.

Kudzu Pies is awesome should you want some baked bread, savory pies, or desserts.

As others say, Pawleys area is just down the road as is Murrels Inlet.  Lots of other places to go in those areas.

For pizza -

La Famiglia Pizzeria 9180 Ocean Hwy #1, Pawleys Island, SC 29585

CArolina Tavern is our new go to, Great food and service.