Screens and kids damage

Depends on what they write with. If it's a sharpie, it's dead.

My HT remains locked and my kids are only in there when I'm in there. Toys and other things are not allowed in there either, so it's not an issue.

If you cannot control access to the room in which your screen is installed, I would say you should stick with an electric roll down type until your youngest is old enough to know better than to mess with it--and put the screen power on a key switch.

No. The best color for your walls is as dark as the wife will allow. Light colored walls will reflect light back onto the screen and wash out the image.

If you really meant what color should you paint the screen, there is a ton of info in the DIY Screen Section at the top of this forum about paints and other materials.

Ideally you would have your walls and ceiling painted flat black, but as this typically is not achievable going as dark as possible will work just fine. If you intend on just projecting onto the wall, the DIY section has some great info on what paints to use to do this. If you do plan on getting a screen, you would want your front wall as dark as possible as well. I am projecting into my living room for a screen with white walls/ceiling and my room lights up when I am watching a movie. It is due to the cross reflection of the image bouncing off the screen and around my room, the darker and flatter the walls, the less this will happen.