Hi justcruzing, sample rates can range anywhere from 6 kHz to 96 kHz, and bit depth can range from 8 bits to 32 bits (floating point).
With sample rate you can have WavePad prompt you to select a sample rate for each new file, or you can specify a default value. To make these selections go to Tools > Options and under the General tab you'll see the options to control this.
For bit depth (and encoding method) this is done when saving a file. After specifying a file name, a window will pop up titled Wave Settings. On the Settings drop down select Custom and you'll be able to select the encoding method including PCM, and you'll also be able to select bit depth and whether you want the saved file as Mono or Stereo.
Hope that helps. If you have any problems using WavePad you can always contact our support team at http://www.nch.com.au/support/supportcontact.html?software=WavePad