Yeah. If you're on DS, check Snemul.cfg in your root directory
it's on the top of the config file:
(If you're on DSi file system, well.. there are problems...)
# Scaling modes:
# 0 : not scaled, the graphics are displayed without change, but the DS screen
# is too small to display all SNES screen. So a part of the screen is lost (see
# BG3SQuis and YScroll for workarounds).
#
# 2 : full-screen scaled, the SNES screen is displayed entirely onto the DS screen.
# The backgrounds uses a pseudo bi-linear filtering to squish the graphics.
# Sprites are squished without filtering. Some pixels are lot.
#
# 1 : half scaled mode doesn't scale as much as full-screen does, so the top and bottom
# ranges of the screen are not displayed and sprites are not squished.
Scaled = 2