mmonika Lead is dangerous only under certain conditions, such as when it is peeling and those particles can be inhaled or ingested, i.e when you handle the door and pieces of paint stick to your fingers, and those fingers can touch your mouth, food...etc. . It is also a bad idea to sand lead paint off.
Lead paint that is not exposed, that isn't peeling, plagues everyone with an older home.. and there's a lot of older homes out there. We aren't dropping from lead poisoning so it can "safe" when untouched.
If you have peeling paint on these doors and what to keep the peeling look, go to a pro. paint shop and get some clear coat to try sealing it up? Handle with gloves and respirator :-) Try not to panic
Backdrop. This set of old garage doors were meant to add dimension and a room, rather than drawing attention, a perfect solution when you have a large wall surface to cover.