here's THE EMU SETTINGS for 128*160:
FRAM SKIP:3

NUMBER OF 90 TURNS:1

MAX NUMBER OF 16KB BANKS TO LOAD: 64 OR LESS

SCALING:

SCALE TO FIT:MARK
KEEP PROPORTIONS: DO NOT MARK
START IN FULL SCREEN:MARK

you could try other settings if they do not work. but plz don't change SCALING and NUMBER OF 90 TURNS settings coz the resolution ratio of GBC is 160x144. That's the most effectively settings.