archey, listen, skip the spdif input, as it accepts only digital info and can't be used for the microphone like you said originally wanted to use. Something with really good preamps is ideally what you want, but unless you are doing pro recording, your don't really need it. $200 is usually what it takes to get a really good 0ms latency card with nice recording preamps for recording analog sound. The specs will not reveal this, your ears will. It makes it harder to track down a good card.Since you want to do gaming too, the needs of the card change. Having some hardware acceleration or at least compatibility for things like dolby digital live or DTS live could be more important than some sound quality.
Another thing, your setup makes a big difference in sound quality and noise levels. Can you please tell me what kind of mic and how you are connecting it to the onboard sound currently? For instance, I use shure sm58 and sm57 mic through a mixer. The mics are hi-z, requiring transforming to low z that a computer could use. The mixer does a fantastic job of doing that. If I used a regular old low-z mic (you can tell because they usually have a 3.5mm or "big headphone" jack (lol sorry dont know the size, maybe 1/4 inch?)) then I would likely get a lot more noise.
Re: creative for recording, I still stand by they are crap. They are best used for digital source recording, as their onboard preamps for the analog side are weaksauce and taint the sound. Just my opinion let your ears tell you different.
check these recording cards out, if when you game, you only need to have your headphones sound good, and are not interested in 5.1, etc. check these out. They are for recording, but still work fine for games.
http://pro-audio.musiciansfriend.com/product/Tascam-US100-USB-Audio-and-MIDI-Interface?sku=502783
http://pro-audio.musiciansfriend.com/product/ART-USBPhonoPlus-v2-Computer-Audio-Interface?sku=180039
one ive actually used and found the quality was really good _for the price_. Best bang for the buck recording wise, it has upgraded preamps.
http://pro-audio.musiciansfriend.com/product/Alesis-iO2-Express-Audio-Interface?sku=485880