I know this is too late for your trip, but for future reference the Speedway KOA is a great place to spend a few days. Take the guided tour of the Daytona racetrack, very interesting even for a casual NASCAR fan. Also close to the beaches and Ponce Lighthouse.
I live in the Daytona Beach area and here are a few places you can try on your next trip. These are all minutes from the beach.
International RV Park (International Speedway Blvd) is good if you're looking for a spot with not a lot of kids. This facility is big rig friendly.
Daytona Speedway KOA is good if you're looking for a spot with a lot of families and kids.
Bulow RV Resort (Flagler Beach) if you're looking for the best value. It's off the tourist path but still a great location.
Seabird Island MH Park (Port Orange) is good for the 55+ crowd. Although it's mostly MH on an island in the intercoastal they do have open lots for less than 50 bucks a night and the fishing is great. Not big rig friendly though.