A: Don't know exactly, but I believe it is large enough to take a standard lock shank. I use mine on the inside of my barn doors, so I use the hasp to "lock" things from the inside.
A: The shackle hole diameter for this safety hasp is about 0.40 inches.
A: Yes you can do that but not with screws shown. What is shown are Zinc plated wood screws, What you need are flush metal screws preferably self-tapping so you can skip the drilling the hole out stage. Self-tapping screws drill and then tap the hole with one screw at a time. Make a small punch mark before you drill so the screw will not walk around before he screw bite gets to start drilling. Drill on the lowest speed possible and be careful that you do not over tighten the screw or it will strip out. Good Luck!
A: With the appropriate fasteners, yes. The included screws are only for wood.
A: This hasp is intended doe use on wood. Will it work for your application? Not well, but you might get lucky. The face of your fridge / freezer is most certainly thin sheetmetal that won't provide sufficient bight for the screws and they'll likely become very sloppy-loose over time. How much time? Immediately to years depending on how carefully you install this, how often you open it, and mostly, how lucky you get.
A: I used mine on a barn door, so the screws had something to bite into. Not sure how it would work on fridge/freezer doors, which likely don't have meat behind the metal skin for the screws to bite into.
A: The screws included with this hasp are #8x1" Flat Head screws.
A: The knob does rotate 90 degrees to lock the hasp. Thank you for your question.
A: Yes, the knob rotates.