rugby will most definitely help your football playing and also the other way around football would definitely help someones rugby!
maddog_mckeown why do you write like an idiot?
Rugby certainly won't hurt your running. I would recommend playing it regardless as its in different seasons than football (where I'm from) You should give it a shot.
There is very little broken-field running in rugby, and vanishingly small lateral running. I suppose the more experience you have with running, the more intuitive it will become, but watch a few rugby games when you can, and see how running occurs in the game. A handful of runners - Shane Williams was one - were renowned as broken-field runners, but it is extremely rare, and largely limited to wings, I'd say. If you are out jinking your way around the field like an American football back, your teammates are not going to be pleased because you will not be working with them. Mark L.