I’d only sit in 4 seats at our local cinema so on the rate occasion we went there, I’d point them out in the plan and ask if they were available. If they weren’t I went to the pub instead.
BFI small screens - front row, centre. BFI main screen - back row, centre, or about 5 rows back from the front centre.
BFI IMAX - rows M or N, centre.
Little cinemas like the Curzon or the Electric in Shoreditch before they made it part of Soho House, any row from row 3 back, centre.
Those Odeon ones with the sofas at the very back, nice seats just in front of them, then normal seats - front row, centre of the nice seats, although that fake leather stuff is quite slidey for people who like to slouch when sitting down, so Odeon’s generally wouldn’t be my first choice.
Edit: I’m a bit picky when it comes to cinema seats…