Welcome, at your advanced age and as wore out and as beat up as you are you may want to find a nice adult tricycle to follow your kids around on. Then put a motor on it to help you get over the curb in front of your house. Make sure you get one with the big basket on it so you can take your walker along with you in case you decide to get off of the trike and walk to a park bench to play checkers with your friends.
Seriously though if you are wanting a beach cruiser check out
e l e c t r a Look in the cruiser section they have some very cool cruiser bikes. They are an upright bike with a foot forward flat foot design that would be right up your alley for cruising with the kids. You can get them in everything from a single speed with a coaster brake up to a nice 21 speed bike for the wild cruise nights on the pier avoiding tarballs.