Hey guys. I live in Charleston so hopefully I can answer some of you questions.
1) Where to stay -- this really depends on budget and if you want to drive. You can save alot by not staying downtown, but you will most likely have to pay for parking downtown if you want to do the historic district. Parking is approx. $16/day in most of the garages or $1/ half hour. There are some cheaper parking places to be found, but that is what I would budget for.
2) If I were going to stay somewhere other than downtown, my first choice would be Mount Pleasant. It is close to the beaches, close to downtown and easy driving to downtown. The next place I would consider is North Charleston, but only the area just around the airport/Tanger Outlet area. I would NOT stay on Ashley Phosphate Road in North Charleston. If you are looking/considering a specific hotel, I would be happy to give you the yea or nay on it's location.
3) Great places to eat -- For a great view, I like Vickery's on Shem Creek. It is in Mt. Pleasant if you're staying in that area. If you want total Southern food, look to Page's Okra Grill, or Boulevard Diner. Also, one of my favorites is Mustard Seed.
For downtown, the options are endless. We have amazing restaurants and are totally spoiled. Husk was named best new restaurant by Food and Wine last year. There are lots of fine dining choices, like Slightly North of Broad, McCrady's, Blossom, Anson's, Magnolia's, Cyprus, Peninsula Grill, Charleston Grill just to name a few.
If you are looking for more budget friendly, look at Fleet Landing (on the water), Pooghan's Porch, 82 Queen (more affordable at lunch). The courtyard restaurant at The Mills House hotel has a wonderful Sunday brunch and great lunch specials.
4) Things to do. Charleston has some amazing County parks with beautiful bike/hiking trails along the marsh. Entry is $1/person.
The carriage rides and boat to Ft. Sumter are always crowd pleasers.
The farmer's market at Marion Square on Sundays has great food and entertainment.
If you have any other questions, please feel free to ask or you can send me a private message.