Shannon, when I do the oil change in my car, I add in 7 quarts. So, 6.1 to 6.5 isn't too far off. Keep in mind that just changing the oil (no filter) takes the 6 quarts. But, adding in a filter, you need to add in another 0.5 quarts of oil. The big tell tail will be what the dip stick says. Fill it to the high end of the fill mark and measure the oil after you have run the car for a minute or so (ensures the oil system has no air in it).
As for your leak, what I would tell you to do is to get some stuff called "GUNK" and spray it in the area around the oil filter (with the filter installed). Try not to hit too many wires. You want to do this with the engine up at temp. Then use a garden hose to spray off all the GUNK that you sprayed on. Take the car out for an afternoon drive (20-50 miles) and then park the car. See where the oil is dripping from now. Pretty much, the highest point where the oil is coming from is the source of your leak. it is possible that the flange for the oil filter is leaking, but more than likely it is the oil pan gasket.
If you need any more advise, make sure to hoot and hollar. We will help you out.
Chris "Thermo" Coleman and Jackie, the 12 XJ