If possible I'd leave your cats with a sitter. If that's not possible here are some things I'd do.
I would first check out the resort to see how clean and how they treat their animals. Reading some online reviews on the resort might help sooth your anxiety too.
I personally haven't had the need to kennel my cat but I would also call them and see what they recommend you to bring. I assume food, whatever medications if your cat needs them, but it's always good to ask and prepare.
We boarded a cat for the first time ever in May. I put a cat blanket that I'd slept on for a few nights in his carrier, which was left open in his "hotel" room for him to use as a bed, and packed several toys, his (prescription) food and medications, feeding instructions, photocopies of his vaccination and microchip registration records, and contact info (our cell phone numbers, family members' numbers, vets' numbers). He wore a collar with ID. They provided food and water bowls, litter and a litter box, more toys and several cat trees. A deposit (50%) was required in advance.
He was there for 9 days and was just fine, though very relieved when he got back home.
I boarded my kitty for an entire month (yes, I know, but there was no alternative!) when I was in the middle of an out of state move and had some other circumstances occuring at the same time. Make sure you pick a reputable place (good online reviews, even better if you know someone whos used them!) and if possible drop by unannounced to see what condition the place is in as far as cleanliness. I wasn't able to do that coming from out of state, but I was comfortable enough from speaking with them on the phone several times that I could tell they were decent people. I packed a 2lb bag of her own food (in case she wouldn't eat theirs they could mix it), a cat blanket, 3 toys, a bag of treats, and her Felliway spray so that she would settle in easier. The only part that bothered me was that they took her collar off (apparently as a safety precaution) but that upset me since I was leaving her so long in a strange area, if she got out she would have no id (she's not microchipped). Luckily, they aren't in the habit of losing cats so all was well and it was an unnecessary worry I called weekly to check in and she was doing fine. Most places supply their own food, bowls, bedding, litter, and scratching posts though, I just packed things because it was a long stay and wanted her to feel comfy there. I couldn't have used a sitter due to my moving situation, but I felt better about boarding her than trusting a sitter to not accidently let her out, or her being scared of the sitter and bolting or something. She wasn't my biggest fan the day I finally arrived to pick her up, but after a few hours of exploring our new home, cuddles, and treats she was back to her usual self
I've boarded my cats for 3 nights when I had to go under radioactive treatments. The vets suggested I'd bring them a blanket with my scent, their carrier and their food. They took care of everything else
Thanks for the thoughts--guess I have been a cat-mom to long and I already have the blanket, felaway spray and their toys. Food is packed as are the snacks. I've checked the place and they even post to facebook so you can see your animals. Daughter is going to stop in a visit-so that should help.