GB airways flights do have IFE... the usual smallish airbus pop down screens. a mixed bag of programs including a film is usually shown on longer runs. Headsets are, If I recall correctly, about £3.00 in economy, free to Club passengers.
The first 8 rows have around 33" -34" seat pitch, seats further back vary at around 30".
If Club is lightly booked, try and grab a seat in the front section of economy.(x-8)