Hi,
I have a cheap Skype mic and a professional Sennheiser mic. When I record with the cheap one the sound is noisy, dull, just like you discribe...
When I plugin the Sennheiser into the same audiocard (old Soundblaster Live!) it's like switching from analog audio to digital CD quality. I could not believe my ears at first.
Quality is not releated to the progam you use but to the hardware, mic and audiocard (conversion analog to digital - amount of bits, quantitizing errors, range, etc...) and of course in the end the compression.
For recording I use the free Wavepad which offers all I need. Listen to KeyGuard demo... narrated that myself (ignore the accent

)
Good luck,
ShAdOwHuNtEr