I recommend you try out DOSBox or VDMSound to get sound to work in the QFG games. The first four QFG games were made for DOS and not Windows so a soundcard such as the Audigy will not work with them since it got no DOS drivers. Also, these games were made for soundcards that used the ISA bus, while these new soundcards uses the PCI bus instead.
DOSBox is an emulator that tries to emulate a complete DOS environment to play your games in. It's a bit tricky to get working and I recommend you also get D-Fend which is a program to configure DOSBox to work with your games. You can get it here: http://dosbox.sourceforge.net
VDMSound is a soundcard emulator which emulates those old soundcards so that your DOS games can run with sound and music. It's more automated than DOSBox so if the games run fine in Windows(can be slowdowns and stuff), I recommend you try it out. You can get it here: http://vogons.zetafleet.com/viewtopic.php?t=2071
Here's a nice beginner's guide for VDMSound: http://vogons.zetafleet.com/viewtopic.php?t=2389