Jeff, Your dad's build and what I can see of his face reminds me of my late father-in-law who passed on at age 75. I think the boys' reaction to his comments was huge!!! They sound like good kids. I kind of sound like your dad, I'm finally building my first layout since our older daughter was a baby (she's 29 now). It is also my first 'big' layout in an 11x11 room. 
I have most of the hard work done, and it's a good thing. Turning 64 on Election Day, my joints and muscles feel it. 
Your dad will remember these moments as long as he lives, I know you will! That's great your daughter has some interest!
I agree with Jim. I didn't need as much backdrop as you will need if you are going to make it go all around the walls. I happened to look at the OGR Forum for sale items at the right time. A fellow Forum member not far away was selling a backdrop he paid an artist to paint on hardboard since he was moving from his house to a condo, and he wanted to go with a custom photography backdrop on his new layout. I had to cut it up, but it has worked pretty well. I have one section to paint to blend in as best as I can. Our older daughter will help me pick the colors and get started once she finishes some other projects. If it hadn't been for the custom painted backdrop that was available at a discount, I would have continued looking at commercial offerings, unless I could have coerced my daughter to help me get started. 
Yes, budget is a big concern for average family guys like us. 
I'm looking forward to seeing what you and your family come up with!!!!
