I wouldn't explain to an extremely non-technical person. Some people can understand it, others would be like "duh, whats USB?", or "Its Korean? You traitor! Buy from an American company like Nintendo." :rolleyes:
I used to explain the GP32 thusly:
"Its like the GBA but more powerful and you can download games and stuff for free".
Then if they were still interested, I would go on to explain about particular games, plus music and videos.
And then, if they wanted to know, I would help them find a place to buy it.
A friend wanted to buy a GP32, years ago, but I talked him out of it as he didn't have internet and I wasn't willing to provide games transfer and other such service to him for free.