There is absolutely no way to predict the traits that a mixed breed will carry. A Bulldog/Cane Corso mix could be identical to either breed, or any combination of their characteristics. It could be as lazy as a Bulldog or as athletic as a Corso. It could be as friendly as the most laid-back Bulldog or as suspicious as a Corso. It could be short and squat like a Bulldog or lean and trim like a Corso. It takes many, many generations of strict breeding to produce reliably predictable offspring, so when you slap together two random breeds, you can't expect any predictability whatsoever.
"This is what I prefer in a dog-short short hairwith minimal shedding"
- Bulldogs are notorious shedders, so you know. Neapolitan Mastiffs and Cane Corsos are minimal shedders during most of the year, but they shed heavily twice a year. The Dogue de Bordeaux is an average shedder.
"want to have protectiveness for the home"
- Most dogs, regardless of breed, will rise to the occasion if necessary. If you're looking for that plus watch dog characteristics (barking and whatever), you'd do well with MANY breeds. There's no need to jump to the more hardcore guard dog breeds like the Neapolitan Mastiff if you're looking for an average guardian.
"with being able to endure some company with our supervision"
- Do you honestly mean "endure," or do you want your dog to be relatively friendly toward the company that you accept? Cane Corsos and Neapolitan Mastiffs are quite suspicious of strangers, and they are much less likely to ever be comfortable and accepting of guests. The average Neo will simply never be friendly toward guests, while many won't even tolerate them. If you like to have company, re-think the Neo, because they were designed to take their guardian job VERY, VERY seriously. With proper socialization, the Dogue de Bordeaux and Bulldog should be tolerant of the company that you accept, while many will be downright friendly. All of these breeds are considered to be good guardians when the need arises.
"easy to house break."
- None of these breeds are known to be easy to housebreak. That doesn't necessarily mean they'd be difficult, but if this is an important criterion for you, then none of these breeds fit the bill. By following the proper method closely, though, you would have success regardless of the breed. Here's the best method for housetraining a puppy:
http://dogstardaily.com/training/errorless-housetraining
"Also I like my dogs to be more on the lazy side as I don't want to have to take it walking all the time but do have a big fenced in back yard."
- That immediately rules out the Cane Corso. They are WORKING dogs. They're powerful athletes who require a great deal of heavy exercise EVERY single day. They will never be couch potatoes. The Neapolitan isn't the athlete that the Corso is, but they, too, require their exercise. All dogs need exercise, but of the breeds you listed, the Bulldog and Dogue de Bordeaux are best suited for your energy level (the Bulldog especially so).
"so am thinking a dog not so quick to want to fight."
- Well, fight with who? As you know, all of these dogs require extensive socialization and training that begins very early in life and continues until death. With that socialization, the Dogue and Bulldog should be at least tolerant of other dogs and people. Canes are more assertive and even with proper socialization, they might clash with other dogs and strangers alike. Neos can definitely clash particularly with strangers.
"understand the importance of firm handling"
- I'm slightly concerned by that phrase. You don't mean anything physical, do you? None of these breeds require any sort of physical bullying. No alpha rolling, no spanking, no staring them down, none of that hoopla. They do need firm owners, but not bullies who get physical. They simply require patient, consistent, experienced, knowledgeable, benevolent leaders. Here's one of my favorite articles that articulately explains the flaws of physical force on dogs:
http://dogpublic.com/articles/article.aspx?sid=14&pid=1640
To be honest, I think that the best breed for you might be the Mastiff (which is sometimes referred to as the English Mastiff). A well-bred, well-socialized, well-trained Mastiff is mellow, laid-back, patient and tolerant. They should get along well with other animals (including other dogs) as well as strangers. They're usually pretty friendly *unless* they have reason not to be. As a member of a mastiff forum, I can't count how many times members have come on shocked because their generally friendly-as-all-get-out Mastiff showed brilliant guardian instincts when confronted with a genuine threat. (In case you're wondering, the typical Mastiff method is to corner an intruder and keep him trapped until you arrive.) They also tend to display all the usual watch dog characteristics like barking and growling at someone near your property, someone at the door, so on and so forth. But when confronted with a friendly, accepted stranger, they're usually docile and loving. They tend to be couch potatoes; they should be walked (daily, preferably!), but if necessary, playing with your son in the back yard will occasionally suffice. A properly trained Mastiff is also quite able to be walked by a teenager; I am a scrawny 17-year-old female with no muscle to speak of and I regularly walk my 170-pound Mastiff. However, they can be pretty heavy shedders, but using a FURminator brush regularly will absolutely cut down on the fur left around your house.