1) Burnout 3, Burnout 4, or Burnout 6. Very cool car racing games.
2) He'd probably like G-Force. An action/adventure with Hamsters as the main characters.
3) There are loads of sports games, but you'll have to experiment to find which ones he likes.
4) There are also lots of games based around animated films: Ice Age, Madagascar, Wall-E, etc. These are suitable for kids.
If you do torrents, there are many games available.
One last thing. You might have to stop into one of the game shops at MBK to get your machine modded in order to play games purchased in Thailand or downloaded.
A good game website that will provide loads of info on all video games is called 'Gamespot'. Just google it and you'll be able to get any information you are after.