You probably have the common extensions hidden (default option for XP Pro). It's the No$GBA file with the gear and notepad icon.
If deleting that file doesn't work, you might want to put the sound options to Digital Mono and Low sampling rate.
Playing around with the No$Zoomer Extra options might also help.
If all else fails, try moving your savefile out of your Battery folder. If it saves and loads afterwards, odds are it got corrupted.
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No$GBA Quick FAQ:
Q1: Savegame doesn't load.
A: Set correct save type. Look
here, divide by 8!
Q2: "Cannot Read Data" error
A: See above!
Q3: Snapshots?
A: Only work for GBA games.
Q4: NDS linking, NDS with GBA slot, Picto-Chat, trading, ...
A: Not yet available.
Q5: When do we get a new version?
A: We don't know. Martin won't tell.
Q6: Donation down?
A: Yes, and we can't do anything about it either.
Q7: Game stops without appearent cause.
A: Turn the Sound option on.
Q8: No$Zoomer fixes don't work.
A: They do only with 2.6a.