Why don't you simply ask him if he would like to go to dinner and a movie? Ask the kids too if they are old enough .. like the Last Mimzy or something...
OK.. it is out of your comfort zone and maybe he will say NO but maybe he will say yes?
You have nothing to lose. He will say yes and then time will tell or he will say no lets just stay friends and nothing changes.
This isn't rocket science.. and you are not pushing, pulling, prodding etc. you are just afraid he will say no. "No" is a word. It isn't the end of the world!
My husband was 18 years my senior.. It ain't the age, its the MILEAGE.