The SB0240 by Creative Labs is a wonderful sounding sound card which even has practical use in modern day towers. I actually still use an Audigy 2 ZS in my work rig which sounds just as good as any modern day card and much better than the line out you get on your motherboard. The Audigy 2 has great support for Windows 9x with VxD drivers and packs in EAX and A3D support (see driver options here). I’m not so sure about DOS support, though. This card doesn’t come with SB16 emulation packed in, but from what I’ve read, there’s a driver available which uses the ECX AudioPCI soundbanks for SB16 / GM emulation (available here).
Untested, but with test upon request.