Ok, good to hear the tank is drilled, so you don't have to mess around with an overflow box.
If you are going to have soft corals, make sure you don't pick fish that will pick at them. Try to find out what kind of lighting your dad had running, if you can find any ballasts or anything, post the info and we can help identify. Pictures would be even better, along with any stats you see.
Is your basement finished? If not, you can usually tell a load bearing wall from a non-load bearing wall by hitting the 2x4s with your fist, and seeing how much they flex. The load bearing 2x4s will be much more rigid. If your basement is unfinished you can pretty easily add some 2x6s and teleposts to support the floor.
That said, I had a 110 gallon tank (6ft though, so weight was spread out along more wall) on the main level of an apartment build in the 50's.
Check if the tank is going to run along the supporting beams, or across them, hopefully you are running across them. One tip is to put a large board under the stand. This way the weight is spread out across a larger surface area, instead of just at the points where the stand touches the floor. (or at least the weight will be more eve)
Don't try to push too much flow through your sump, if you have 2 holes in the overflow I would use them both as drains (instead of traditionally 1 drain, 1 return) and just push as much water as 1 drain can handle, then in case of a drain line failure your other drain line will be able to handle the flow.
You could use the hole at the back of the tank for a closed loop manifold for water flow if you want. I have a sequence baraccuda on a closed loop manifold and am happy with it, I have 7 1/2" loc line nozzles I can point anywhere to customize my flow. Tunze streams would be awesome, or seio's for cheaper but not as good.
I would put as big of a sump as you can fit, and put a refugium in it, and buy the best skimmer you can afford. If you can't afford a good skimmer, don't start the tank until you can. I use an ASM, they are cheap but good IMO. A G4X would be awesome on your setup, especially if you are going to get some larger fish that eat a lot and waste a lot.
http://www.asmskimmer.com/catalog/pr...products_id=33
Euroreef, bubble king, and deltec are others that are great skimmers, but for me they are cost prohibative.