We (group from my office) once booked with Continental, paid Continental, but flew Virgin Atlantic. This was done through http://gotoday.com The seats were back in Economy ... not a lot of leg room ... but you could try to get the seats at the front of the section, if you book early, and that always means more legroom. My very tall friend Tony (he's 6 foot 2 or 3 or something) ended up changing seats because the elderly woman in front of him (probably 4-foot 11 inches, 85 pounds soaking wet) immediately tilted her seat all the way back and fell asleep. He basically couldn't breathe - but the flight attendant was quick to reseat him, which was nice.

You have some time, try all the discount places, just in case!

We (Paul and I) flew over with US Air - not to be recommended. Our flight from Boston to Philadelphia to get the connecting flight to London was delayed, we were told our connecting flight would be held for us, raced literally as fast as I could go through the airport ... to find out it had just left. With no apology from the people behind the desk. So we had to hang out at the airport for 5 or so hours for the next available flight ... not fun.