Jerking your seat back and spilling someone's food is not reclining, it is assault.
Both the person who did it and the airline should make up to the person behind, the airline is mentioned because it has the ability to identify and detain the miscreant and may extract reimbursement from that person.
If someone is giving you grief about space, ask to switch places.
Perhaps we need to have half the plane, maybe the right side, with all seats that don't recline. Then most people can choose.
And, IMHO, no one regardless of size has the right to both expct the person in front to sit upright and also recline his own seat.
More travel tips:
http://members.aol.com/ajaynejr/travel.htm