16-bit or 24-bit converters?
There is a lot of bad information and audio phoolery available on this topic, but if you're doing one channel of digital audio, 96kHz and 192kHz sample rates are silly. Human hearing extends to 20kHz. To satisfy Nyquist at 20kHz, we need a sampling rate greater than 40kHz. CDs are 44.1kHz, and 48kHz is another common sampling frequency. 

Now, let's recall that digital audio is a discreet signal, not continuous. This means that is has a value at each sample time, and is undefined at all other times. For a bandlimited signal, sampled at or greater than Nyquist, there is only one signal that passes through each of these discreet samples. Any other signal that passes through all the sample points cannot satisfy Nyquist. The only reason to sample at 96kHz or 192kHz for a single channel is if you're oversampling with a low bit depth ADC. That's also silly, and we'll go there next.

We just discussed how a series of discreet samples matches exactly one signal. This is independent of bit depth. That does not mean bit depth doesn't matter. The conversion to digital introduces quantization noise. Quantization is noise introduced to the digital signal by "rounding" it the closest digital value, as shown in this image shamelessly stolen from Wikipedia.



Quantization noise is directly related to bit depth. It should be fairly obvious the more resolution(values to round to), the lower the quantization noise. A higher bit depth makes for higher full scale resolution. Higher resolution reduces quantization noise by having more values available to closely match the signal's value at a sample. Lowering quantization noise lowers the noise floor, and increases the signal-to-noise ratio (SNR). 

Can you hear the difference between 16 and 24 bit quantization? I'll bet anything you can't. It's for a guitar, and guitars are not known for their dynamic range. A professional symphony? Maybe, without dither. The 16 bit noise floor is far enough down it's unlikely to be discernible, but the difference will be measurable. 

In summary, my vote goes for 48kHz sampling rate, and 16 bit resolution. I strongly encourage anyone interested in this topic to watch this video.