The D2000 have a good soundstage, M50's lacks on soundstage.
M50's have better isolation.
You could save a few dollars and get semi-open cans.
Should not have to worry about sound leaking to other rooms.
Panasonic RP-HTF600-S, semi-open
(add Velour pads for better comfort)
Superlux HD-668B, semi-open
Comes with a 3' and 10' cable
Samson SR850 semi-open (made by Superlux)
10' fixed cable