Here's another way, if you're ok with poking around in DOS mode.
0) download this program, unzip it somewhere in your path
http://www.waste.org/~winkles/fuzzyRename/insert.zip1) in a DOS shell in your ROMs folder, type this:
"dir /b > moveme.bat"
2) edit moveme.bat, do a search/replace of ".zip" with ".png c:\mame\snap", save and quit. [you may have to edit that path of where you really want your snaps to end up]
3) now type:
insert
at the prompts, type in "moveme.bat" for the filename
for the col#, put in 0
for the text string put in: "move " [note the space at the end!]
insert.exe will then jam some text into the front of each line of your batch file, so the end result should look like this:
move 005.png c:\mame\snap
move eggor.png c:\mame\snap
etc
etc
etc
etc
4) run that batch file in the folder you've got your full collection of snaps in, and it'll move 'em all.
hurray for DOS!