Basically, the microphone preamplifier that is built into your soundcard is meant for those little $10 mics used for gaming. It will totally suck for recording. The first step, in my opinion, is to get a preamp of some sort and use the line-in on the soundcard rather than the mic-in. In the budget category, I would recommend the Studio Projects VTB1 preamp ($99). If you need more than one channel, the M-Audio DMP3 is nice, or you could get a small mixer (Yamaha, Soundcraft).
Personally, I have little direct experience with Samson mics, but I have a pretty poor opinion of their product line in general. That mic might be just fine. A condenser mic would provide you with greater detail, but will also pick up more ambient noise (like your computer fan, etc.).
Other things, like room acoustics, soundcard quality, and monitors may also need to be addressed.