Are you only looking for pistols? Shotguns are a great choice for home defense because of the area that is covered by the shot. Meaning one shot and you have a much better shot to hit a target.
If you're looking for pistols, I'd agree with a comment above. You, for the most part, get what you pay for. I would look at the name brands and figure out what's best for you and try to shoot different brands/calibers.
Also, is anyone else possibly going to use this firearm? Make sure they are able to rack it. I had to buy a new pistol for home defense because my wife could not pull back the slide on my Springfield XD9 subcompact. Make sure they are able to try it.
And as I mentioned above, this is just strictly MY opinion(and may not be the most popular one) but with small children, Glock may not be the best choice. They are an extremely popular pistol and a great pistol but their safety(only on the trigger) scares me with a growing up fast 8 month old girl in my house. In the end, you are the ultimate safety and should never rely on a mechanical device to stop the firearm from shooting.
This question is the most popular in my concealed carry courses and impossible to answer. Most gun ranges(call and check) allow you to rent firearms so it's a great opportunity to try before you buy.
Or, if you're going to take the classes before hand, call a NRA instructor and see what types and how many pistols they have to rent for the class. I know you're not wanting it for carry purprose and that's the main reason people take the class but it covers the safety, proper handling, safety, cleaning, safety, ammunition, malfunctions, etc. Did I mention safety? :)
It was vague, but I hope it helped.