Folly beach is really a nice place to visit and have fun for. It is also known as "the edge of America", Folly Beach is great for families or large groups of beachgoers because the pier area has a large parking area, a covered shelter, handicapped accessible restrooms, showers, a restaurant and a gift and tackle shop.

Wild Dunes also. You might look at VRBO. I'm sure you can find something, but beach houses tend to be rented early for the best selection. I'd hop right on it.

Another vote for Wild Dunes.

Third vote for Wild Dunes - lovely "gated" property with a variety of rental condos and villas, terrific expanse of beach and easy ride to Charleston.

We also love Wild Dunes-close enough to Charleston to go eat and see the sights. We have gone twice-once rented a condo and once a house. There are lots of restaurants nearby.

I'm partial to Kiawah Island, right next to Seabrook, but Wild Dunes is closer to Charleston. The county park at Follly Beach is presently closed due to erosion with plans to reopen sometime in the summer of 2013, so if you choose Folly Beach make sure that any close beach access to your rental does not involve county park, just in case it is not finished by June.

I do recommend using a satellite map and any info from whomever you are renting from regarding how close beach access is. Much of the dune structure in SC is protected and thus the paths to the beach are boardwalks spaced along the beachfront. With kids and all of their stuff...it could be a long walk (or carry with the 2 yo) depending on location. For example, the first rental for Wild Dunes I pulled up that sleeps 9 is 900 yards to beach (1/2 mile). If renting directly from Wild Dunes Resort (or anyone for that matter) note their policies page carefully for cancellation, deposit forfeiture and per night credit card incidental
authorization holds (90 per night, held extra 5-7 business days on a debit card. That's $560 - not chump change in my opinion - out of someone's checking account for an extra week if you use a debit card.)

A word about the beach...most Charleston area beaches are 'safe' beaches most of the time. It is the ocean, however, and awareness of the weather, winds and any advisories is your responsibility. I believe the beach is a pretty gradual slope in most of the area leaving wide beaches at low tide and tide pools that little kids like to play in.

The Aquarium in Charleston is great for the whole family, fwiw.

Are there parking areas at the public beach access points? That is true in other places we've been. BUT it is a very good point. Our condo is oceanfront and first floor, but we have to walk to the dunes crosswalk. Gone are the days you could play on the dune.

dsgmi makes good points about beach erosion in Folly - be sure to know what the beach is like in front of your property. There are places in Folly where there is no beach at all at high tide. Folly also has somewhat rougher water than Isle of Palms. You will also encounter more smokers on Folly as smoking is not prohibited in restaurants as it is in other Charleston beaches.

Wild Dunes is on Isle of Palms. To me, being behind a gate on Isle of Palms is unnecessary and adds to your travel time to Charleston and restaurant options on Isle of Palms or Sullivan's Island (Wild Dunes is on the far east side of the island).

We like both Folly and Isle of Palms, but would choose Isle of Palms given your situation.