score:7
You aren't going to see a specific difference between Boeing and Airbus for this. Every aircraft can be configured differently depending on the airline's wishes and it has little to do with who makes the plane.
The best thing to do for this kind of information is to check a website like seatguru.com. You can find the seat map for the aircraft operating a particular flight and note the pitch (legroom) and width in the top right of the page.
Note that airlines often have different configurations of the same model aircraft. For one of your examples, Qatar has three configurations of the 777-300ER: V1, V2, and V3. V1 and V2 are a 3-4-3 layout in economy with 17" width seats, while V3 is a 3-3-3 layout with 18.5" seats. You can often see which configuration the airline expects to use by attempting to match the seat map on the airline website with the map on SeatGuru, but note that the airline does not guarantee this (they, in fact, do not guarantee the type of aircraft at all) and may change to a different aircraft or seating configuration at any time.