With this budget, you can forget about higher display resolutions. The cheapest models you will find with anything more than 1366x768 are in the $700 range and up.
Acer V5-552: $399
- 15.6" 1366x768
- AMD A8-5557M (2.10GHz)
- 4GB RAM
- 500GB HDD
Acer V5-572: $480
same as above, but:
- Intel Core i5 3337U (1.80GHz)
- 6GB RAM
I have an Acer V5-572 myself (although with better parts: 1080p IPS screen, 8GB RAM and Geforce 750M) and it's a really decent model. It's not too heavy (2kg = 4.4lbs) and the quality is ok. Battery life is good (my model does the advertised 5 hours while WLAN surfing).
The above model with the i5 will be a bit faster in everyday use and will probably have a better battery life. But if he intends to play the occasional game, then the AMD would be better.