[size=-2](damn my pages are old, gotta do something about that)[/size]
For lightgun games, win98, and multiple mice, the most reliable settings are:
mouse 1
multiplemice 1
lightgun 0
lightgun2a 0
lightgun2b 0
and probably
switchablemice 1
To test which physical has what number, the easiest is to start a game, go into Inputs (this game), and remap something to a mouse press. You should get a couple mice's numbers, the non zero mouse number is that mouse's mouse number in analog+. (Remap to normal by pressing enter then esc.) Remember to remap the mouse buttons to the game buttons (
ctrlr ini's are GREAT for this.)
With switchablemice enabled, there is a new menu item in mame's in-game UI, "Mouse Controls". Go into there and set each player to the correct mouse. (Instead, you can hand edit the cfg/*.ana game file, made after playing a mouse/lightgun/spinner/TB/360wheel game.)
Let me know if this doesn't help. (Please, include the total number mice installed, directX version installed, and the noted above options settings.)