Midimeow is an easy-to-use tool to converts:
Midi to Mp3 at 15 different bitrates
Midi to Wav
Midi to Ogg vorbis at more than 10 different bitrates
It allows to change the rate of the output (3 rates available)
The number of channels (mono or stereo)
Mini-mixer to change mixer settings from the program, or call the volume control from the sound card from the program.
A sound card with midi output and winmm.dll are needed
Free options are not time limited !