I live in Mt Pleasant and work in Downtown Charleston.
Charleston Place is really nice. Great shopping righ there, too.

There are the carriage tours all over the tourist district. I've done one when I had out of town visitors. It was very nice. My favorite are the night walking ghost tours. I've done more than one of them and would go again.

Magnolias is a tad fancy for me ( have you seen the commerical where "elf food" is mentioned ) but has a very nice atmosphere. I prefer less fancy. My favorite restaurant downtown is Meritage on E Bay St. They often have coupons on restaurant.com and their food is incredible! They also have a good 2 for 1 happy hour, which is a great deal! For a little beit of fun nightlife, stop at Tommy Condon's on Church St to listen to a great Irish Band ( They play Wed-Sun

)
If you have a car, there's the Plantations to tour ( Middleton and Boone hall ) They're beautiful! Boone hall is about 5 mins from my house! Also, the beaches on Isle of Palms and Sullivans Island. This time of the year, you'll probably see a bunch of dolphins just off the shore on Sullivans. Poe's Tavern on Sullivans is a great local hangout.
Shopping in Charleston is nice with lots of boutiques and then good chain stores. For the most part ( IMHO ) most of the market stuff is crap directed towards tourists and cruise shippers but the sweet grass baskets are a very popular local souvineer and are hand made here.
Have fun!