It's only been about 4 years since we were tenters, and we've done that a lot longer than this RV-ing stuff
The main categories in my mind are:
Shelter and sleeping gear (and remember cots or air mattresses or something to make the ground more comfortable), a little broom and dust pan will be helpful to keep the tent clean inside - find a set at the dollar store.
Hygeine and toiletries - a means to carry the gear to and from the bathhouse like a tote bag or bucket organizer thing is really helpful. Also, flip flops for showering in...or a small non-slip bath mat works too. (not sure around your parts, but you may want to pack some quarters for showers...I know up in our region VT state parks have coin op showers, so I would guess there might be some others out there with coin op as well) And don't forget your towels (oh, and a way to dry them...we use the older version of this:
Ikea Drying Rack (and great, this one has more space than ours...now I want one!) Or a clothesline will do, but some parks don't allow them, and with a rack you can move your stuff around to a sunny spot or under shelter if it starts to rain.
Cooking - a coleman stove and a little propane grill will cook just about anything. As was mentioned, do your meal planning in advance and keep it simple. Some weekends we cook everything on the grill and don't even break out the stove. Using foil packets to cook veggies is sweet with little cleanup. We even have done taco meat using a foil packet, grill the shells (watch them closely, though! they flame up quickly...don't ask how I know that...) So if you're only grilling you literally just need a spatula and tongs. Paper plates and plastic cups and silverware will be sufficient for the first few times out. A tablecloth for the picnic table is nice to have
And I'll respectfully disagree with Bama Ed (sorry!) and say that the Fort might be easier for your first foray since you have fallback restaurants at the ready if a meal doesn't go as planned, and those bathhouses are quite nice.
And light, I almost forgot! (how could I forget...I just spent the last 7 days in the dark after a freak early winter storm!) Pick up some decent flashlights and a coleman lantern. Light sticks are also helpful as little night lights in the tent at night. We used to attach the light bracelets to little loops inside of our tent. Oh, and a watch with illumination is helpful for sleeping with so you can check the time easily.
If you find you love camping, think about an EZ up awning (or something similar). This makes or breaks camping in the rain - put it up over the picnic table and you can still cook, eat, play cards, etc. and feel sorry for the poor prople holed up in their tents (we were of the latter group for many, many years until the lightbulb went on!)
And don't forget a spare pair of shoes for each child...camping makes for fun adventures that often involve mud or water...at least for my DS!