For my guest Win 95 OSR2 (4.00.950B) I used this driver: VXD_A400.exe from Realtek (e.g available via their website in Twn or google for vxd_a400.exe). Installation is pretty straightforward , takes a couple of reboots and you end up with sound (Realtek AC'97 Audio ) and a bonus thrown in. It is good enough to play the Win95 funstuff demo Goodtime.
Websites:
http://www.opendrivers.com/categorycomp ... page1.html
http://www.realtek.com.tw/downloads/dow ... n=false#AC
Oh - it does keep my Win XP SP1 host busy !