Neophyte question about DAC's...

If it is taken from a digital feed then yes, it could.

Compared to feeding the sound out of a PC's headphone jack, a USB DAC can be a major improvement. I am quite impressed by the tiny and inexpensive nuforce USB DAC I purchased earlier this year in order to listen to Pandora off a notebook PC thru my patio speaker setup.

Internet Radio is of a very low quality, equivilent to an MP3. I would not suggest investing alot of money into a dac solely for this purpose.

You could also try something like the HRT Streamer II. Music Direct offers these and has a 30 day return policy, so if it doesn't make a difference, not a prob...

I just posted this a bit ago regarding this very question. More of a way to show what you can get out of internet radio, especially Pandora which I use exclusively now. It was recorded on an iPhone but still, you may get the idea.

http://www.youtube.com/watch?v=-betjXo_kQU