The inside of a Yaris, even the 3-door model, is quite roomy for the size of the car, lots of head space and the split rear seat that folds down is very convenient. I would think the 5-door version would work great for you, just a little bigger and allow you to deal with the car seat (if you are using one still) in the back. I don't know how they compare safety ratings wise, but I was rear ended quite hard in my 3-door and didn't suffer any damage to the frame, just the bumper, light, and rear quarter panel that that other driver's insurance paid for. My sense (personally) is that in a minor accident, most cars will be pretty equivalent. In a very serious accident, especially with a much larger vehicle, ANY subcompact or compact is going to probably come out on the losing end, so I do things to protect myself, like driving defensively and alertly. There are a lot of things you can do to protect yourself (though obviously you can't control all scenarios). So if you are planning on a subcompact or compact, pick the one you like the best and go with it. I personally think hatchbacks are nicer because you have more storage/transport space. Also, the subcompacts are awesome in that they have a very tight turning radius and can fit almost anywhere, so if parking is tight that slightly smaller footprint might sway you.