Hi, Rob. You have asked many questions and opened a lot of doors. There are 2 paint strippers that I suggest. These are Citristrip and Peel Away. Citristrip is good for up to about 5-7 coats of paint or finish and Peel Away takes over from there. Citristrip is N-methyl pyrrolidone based and non-toxic but you do want to have good ventilation. Peel Away is lye based. You can leave Citristrip on for one day with no problem and Peel Away on for 2 days.
I have a lot of safety concerns with methyl chloride based strippers and will not use them. Other strippers do work slower than methyl chloride but do the job. Both suggested strippers will give a chemical burn so you must use gloves and eye protection while applying and removing them. And you must keep the kids away from the area where they are in use. Our daughter has an older house than yours and we have 2 grandkids so I can relate to your problems and concerns.
As far as lead, you will be safe if you keep the lead based paint tied up in a liquid. Lead dust is a problem along with injesting the solids. The liquid/gel strippers keep the lead in suspension so there is relatively little lead hazard using them. You do have to dispose of the stripper/paint goo responsibly and according to your local requirements. Heat guns can be a problem under certain conditions. If you get the old paint up to 600 degrees, the lead will vaporize out of the paint, become airborne and contaminate whereever the vapor lands. The stripped residue holds the lead if you don't get it too hot but the residue can be dusty so the liquid strippers are a better answer as far as I am concerned. Never scrape or sand suspected lead based paint. Aside from the lead dust going into the air and contaminating everything, sanding causes your woodwork to lose defination (sharp edges and corners) so again the liquid strippers are a better answer.
One other point about lead is that it's effects are much more pronounced in infants and children than in adults. Even vacuuming up dry residue can put lead in the air if your vacuum does not have a HEPA filter and you do not want to take a chance with their young brains and bodies.
The biggest problem with the suggested strippers is that people do not give them time to work. With both, you glop them on and let them work. With Citristrip, brushing back over it allows the chemical that does the work to escape so don't do that more than absolutely necessary. With Peel Away, you put their special paper over it to keep the lye working on the surface. After a day or 2, you come back with a putty knife or other tool and remove the paint/stripper goo. A stripping pad works well with Citristrip removal. Then dispose of the goo in a responsible manner as above. Cheap white vinegar can be used to neutralize Peel Away. It is a good idea to neutralize the wood and then rinse it with plain water when using Peel Away. Citristrip's Paint Remover Wash or mineral spirits/paint thinner shows up areas that were not completely stripped and gives you a much nicer surface to work with for the rest of the finishing process.
I'm not familiar with f5f but there are a lot of new and regional stripper products out there. Citristrip can be purchased in about any home center. Peel Away can sometimes be found in home centers but is more available thru paint stores and is also available via mail order at www.woodcraft.com.
Good luck and let us know if you have any more questions.