I tried a couple NES emulators and have decided on VirtuaNES.  I just can't get it to work with MAMEWAH.  I'm using VirtualNES 0.92e from 
www.screenshotarchive.com and MAMEWAH 1.51
I found settings for previous MAMEWAH versions at 
http://webpages.charter.net/rbecker5/emulators.html that should work.
Show DOS Box = 0
Send ROM Path = True
Use Long Filenames = True
Send ROM Extension = True
I started with a copy on my mame.ini and saved it as virtuanes.ini  with the following changes:
emulator_executable                       C:\Games\Arcade\NES\virtuanes092e\VirtuaNES.exe
send_rom_path                             1
send_rom_extension                        1
quotes_around_romnames                    0
long_filenames                            1
show_dos_box                              0
When MAMEWAH tries to fire the game through VirtuaNES, I get a VirtuaNES error saying "don't open a "rom_xx" -verify roms file".  Most of the time this is a double error.  If I open the game with just VirtuaNES, close it, and then try with MAMEWAH, I can get it to a single error (and the game loaded) only if I show dos box.
Needless to say, I'm baffled.  Is there a remnant from the copied mame.ini calling for VituaNES to verify the ROM?  Maybe the new version of MAMEWAH changed something?
[edit]
I just noticed the log file for MAMEWAH:
10/7/04 12:38:12 AM C:\GAMES\ARCADE\NES\VIRTUA~1\VIRTUA~1.EXE C:\Games\Arcade\NES\10-YARD FIGHT (U).nes
10/7/04 12:38:14 AM Error 75 Path/File access error in EMU_VerifyROMs
It doesn't help me, but maybe someone else can make sense of it?  If I just open the roms directly with VirtuaNES, they play great.