If you're choosing between these two window seats, I'd pick 2L for the quieter front cabin and quicker meal service. If you prefer to be further from a galley and lavatory (not that either is much of a factor in row 2), you could pick 8A, but that puts you closer to the Y bulkhead, if that's a factor for you.
I just flew LHR-IAH in 1K and might have been slightly annoyed by galley and lav noise/commotion on an overnight flight but had no issues with it on the daytime flight when I wanted to stay awake anyway.