First let me say that DH and I went to WDW for 4 nights, 5 days in March without kids and had a great time!!
But, as another poster said, if you want him to fall in love with the world I think it's most likely to happen by him seeing through the childrens eyes. The wonder, amazement and magic with kids is priceless.
Perhaps maybe you should take the kids and kind of ease him into it. You could do an easy relaxing day in each park, no rushing, no commando park touring, just a stroll through the parks. Take lots of visits to the pool etc, maybe spend a day or 2 at the beach etc.
My hubby wasn't the biggest disney fan in the world before our 05 trip. After that trip, when I began planning our 06 trip he kept saying "we aren't going to Disney World every year!"
At some point during that 06 trip he began to "get it!" Now he's his own little disney addict, all be it very quietly. It was even his idea to buy DVC!!! I still can't get over that!!
WDW without the kiddos was a completely different experience. I could totally see someone who isn't a disney person HATING it without kids! Think of all the lines. crying, screaming kids, exhausted, rude parents, getting hit in the ankles by countless strollers

If he doesn't go into with the right attitude it could turn into a disaster.
We went 4 times with the kids before our no kids trip in March. We knew what we want to do, where we wanted to eat and all the more grown up things we wanted to do before hand. A lot of that came from the experiences we had with the kids. We really had a great time and we'll definitely do it again!
Good luck! I hope your DH ends up being a coverted Disney Addict too!