Audio formats with a sample rate higher than 48000 Hz, or with a bit depth higher than 16-bit, are meant for professional use in studios for example.
If you don't have to deliver to, or work in the professional audio industry, then selecting sample rates higher than 48000 Hz, or bit depths higher than 16-bit, makes no sense at all and is a waste of processing power and memory.
Recording directly to MP3 only works with 16-bit Audio. If you want to record other formats then switch to recording in WAV format.
When recording directly to MP3, if the audio recorder says that the audio format is not supported, then select either 16-bit, 44100 Hz (CD Quality), or 16-bit, 48000 Hz (DVD Quality), whichever best matches what's playing back.
If you are playing Quadraphonic or Surround sound then the audio recorder will record as WAV. Change to Stereo if you want to record directly to MP3.
If you record in WAV format then you can convert (either automatically or later) to what ever format you want.
To change the audio format used by playback devices and/or the speaker configuration in Windows Vista or Windows 7, follow these steps:
Right-click on the little speaker icon in the taskbar of Windows and select Playback devices from the menu that pops up.
Highlight the device you want to change the audio format for (usually the Default Device) and click on the Properties button.
On the Properties dialog click on the Advanced tab and select the desired audio format (sample rate and bit depth) from the drop-down box.
Highlight the device you want to change the speaker configuration (Quadraphonic/Surround/Stereo) for (usually the Default Device) and click on the Configure button. If the button does not enable then your device doesn't support configuration.
On the dialog select the configuration you want