I recommend you use the Boxer frontend with DOSBox. The following is my configuration file. Simply save it as Default.conf (to use with Boxer) or dosbox.conf (to use without Boxer) in the same directory as Boxer and DOSBox. It already mounts drive C: as a hard drive, and D:, E: and F: as CD-ROM drives. It also activates the 2x filter, which you can deactivate in Boxer or by changing the line scaler=advmame2x to scaler=normal2x.
# Config file created by Boxer Version 0.61.6
[sdl]
fullscreen=true
fulldouble=false
fullfixed=false
output=surface
hwscale=1.00
autolock=true
sensitivity=100
waitonerror=true
[dosbox]
language=
machine=auto
memsize=16
[render]
frameskip=0
snapdir=C:aspect=false
scaler=advmame2x
[cpu]
core=normal
cycles=6000
cycleup=500
cycledown=20
[mixer]
nosound=false
rate=22050
blocksize=2048
wavedir=C:
[midi]
mpu401=true
device=default
config=
[sblaster]
sblaster=true
base=220
irq=7
dma=1
sbrate=22050
adlib=true
adlibrate=22050
adlibmode=adlib
cms=false
[gus]
gus=false
[speaker]
pcspeaker=true
pcrate=22050
tandy=true
tandyrate=22050
disney=true
[dos]
xms=true
ems=true
[modem]
modem=false
[autoexec]
mount c c:mount d d:\ -t cdrom
mount e e:\ -t cdrom
mount f f:\ -t cdrom
c: