Wil, JRT's are fun dogs but they do not make good pets without lots and lots of training. They are generally not good with children. I know you don't have any now but your step-children may have some before the dog dies.
JRT's are extremely hard working but they do not get along with other dogs and often pick fights with dogs that are much larger than they are. If not given enough attention they can be destructive.
I was thinking about getting a JRT because of that dog Eddie on the "Frasier" show but after looking further into the subject I decided to go with Shelties. They are beautiful dogs and are well-mannered.
Here is what wikipedia says about JRT's:
Jack Russells are first and foremost a working terrier. Originally bred to bolt fox from their dens during hunts, they are used on numerous ground-dwelling quarry such as groundhog, badger, and red and grey fox.[citation needed] The working JRT is required to locate quarry in the earth, and then either bolt or hold it in place until they are dug to. To accomplish this the dog must bark and work the quarry continuously. Because the preservation of this working ability is of highest importance to most registered breeders Jack Russells tend to be extremely intelligent, athletic, fearless, and vocal dogs. It is not uncommon for these dogs to become moody or destructive if they are not properly stimulated and exercised as they have a tendency to bore easily and will often create their own fun when left alone to entertain themselves.
Their high energy and drive make these dogs ideally suited to a number of different dog sports such as flyball or agility. Obedience classes are also recommended to potential owners as Jack Russells can be stubborn at times and aggressive towards other animals and humans if not properly socialized (a process that should continue throughout their whole lives). Despite their small size these dogs are not recommended for the condominium or apartment dweller unless the owner is ready to take on the daunting task of providing the dog with the necessary amount of exercise and stimulation. These are truly a big dog in a small package, and most suffer from a "Napoleon complex", which can sometimes lead to trouble involving larger animals. The JRT owner must be aware of these tendencies and be the cognizant party in many situations.[2]
The Jack Russell Terrier can cohabit with well behaved children but both dog and child need to be properly introduced and educated on how to behave towards one another. JRTs are also extremely loyal towards their owners, and highly territorial. If a Jack Russell decides that something belongs to it even the most persuasive owner is unlikely to convince them otherwise.[citation needed]
Despite some of these negative traits JRTs are exceptionally loving, intelligent dogs who have the ability to entertain their owners for hours with their comical antics.[citation needed] To understand the Jack Russell temperament, it must be remembered that they are first and foremost a "working dog." In other words, they were bred to aggressively run, chase, and flush out fox and badgers in the great hunts of England. These traits, so passionately guarded by Jack Russell breeders since the 19th century, have delivered to us a dog that is fearless, happy, alert, confident, intelligent and lively. A dog that is ready to meet the world on a moment's notice; this is the Jack Russell temperament in a nutshell.