However, I would not buy one of those because their shelf life is about up.
The hard drive size is only important if your 12-year-old wants to download games off the playstation store. I like to download games off the store because I personally have more fun with six $10 games than the vast majority of $60 games. The playstation store also has many PS1 games, and some of those are awesome. If your son has a PSP, he can place any PS1 game (from the store) onto it from his PS3.
http://www.gamestop.com/browse/playstation-3/systems?nav=138d-c4&loc=storefrontheader_row0_col1+cs_ps3
The second playstation in the link is a refurbished 160GB system for $220. It should be awesome, but it looks like it doesn't come with a controller. The playstation above it is brand new, and comes with a controller, but is $30 more. Controllers are $50, so the new one is a better deal.
I would only buy a new playstation (or any console) or a refurbished playstation because you never know how the previous owners treated it. An old one can easily die in a few month, but a new one or refurbished one will last years if you take care of it.
One of the reasons consoles die is because people leave them on for a long time, so make sure to go to System Settings, and set the timer to turn off after X hours of no activity. You can have two different times, one for games and one for movies.
The Playstation is great for Netflix and Amazon, if you're into those things. My wife and I really enjoy them.
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