you'd have more options at hand if you used a different mame build such as groovymame (not so easy for new users but a large amount of added options) or mameuifx (easier for new users but less options than groovymame), as these allow a soundsync feature which will let you force all games to run at 60hz but remain smooth (at the expense of the games either running faster or slower than they would do at the actual arcades). im actually not sure where official mame stands on this anymore. perhaps the answer lies here: http://geedorah.com/eiusdemmodi/forum/viewtopic.php?pid=321#p321 (puts on crash helmet...)