The reason this is a complex issue is that, yeah, they'd all rather have a burger than a spreadsheet, but when you give a starving child a meal, you are doing a great thing, but in all seriousness he's just going to need another meal in 4 hours. Are you just going to feed this kid with donations forever, or are you going to try to spend that money on the sorts of investments that will allow him, his family, his town, his country to survive on their own?
The power of the internet is really hard to even understand. Its usefulness in the scope of human rights, peace/justice, art and science really can't be overstated. In the end it will make the printing press look like a minor footnote in human evolution. And for those that say "traditional" means of education are just as valid...have you had to buy college textbooks lately? The shit costs *way* more than a $200 computer. And shipping them to Africa...how much does that cost? To update a book you have to re-print the sucker, but a computer can be updated via network. Computers are also much better for learning things on your own, at least for me. What you are trying to teach these people is really important stuff like water treatment, disease prevention, first aid, farming, language skills, really basic, but really important stuff.
As for being able to buy/build something better from off the shelf parts...you truly are a total tool for thinking this. When was the last time you saw a laptop for sale with a hand powered generator built in? Personally, me, never, and to power a 2 ghz windows machine with a GB of RAM by hand would probably be impossible. You'd need to have dudes on bicycle generators pedaling away the whole time. Consumer laptops for us rich westerners are a completely different products. They are fragile, unreliable, basically the Kleenex of computing. A new iBook is great for me, but these people have different needs totally. These systems will run on less power in a day than my computer consumes in a few minutes. The OS is no frills, but solid. NASA doesn't send Windows into outer space, or even Linux. A similar situation applies.
Think of the C64. That thing was on the market for f*cking *ages*, the same computer. No changes. Now a laptop is considered uselessly slow in 7 years or so despite it being literally millions of times more powerful than a C64. This is the sort of product that the 3rd world needs, and in some ways all of us, honestly. We can't all go chucking $1000 laptops every few years because the USB ports blew out, or the screen cracked, of the shift key doesn't work, or "now that have a prettier one", because the landfills, not to mention credit cards, can't keep going like this forever.
These people need food, medicine, etc, but they also need to be able to figure out how to survive well without donations someday.
While it may seem like I think that I just laid out a case for these little green computers, the truth is I'm not really sold on this particular idea just yet. I do think however its worth trying as part of a multi-part strategy.