which one is better? a macbook or a sony vaio?  

Well it completely depends on your needs. Sony Vaio is a Windows based laptop while macbook is Mac based. If you are more into multimedia and graphics designing stuffs, I would suggest that you go for Macbook. But if you want something for regular use, Sony Vaio would be the definite choice because of all the availability and compatibility of hardwares and softwares in the market. Rest is upto you to decide.

vaio = windows
mac = OS X

totally different, for home use i would recommend neither and get a cheaper PC. if you are a graphic or web designer then i would recommend a mac as they are recognized as aesthetically superior. however, for general ease of use i would recommend the vaio with vista and now you get a free upgrade to windows 7 i think, which i would definitely recommend!

generally i think macbook as other apple products are too expensive for real performances they offer tot heir users and so in amny cases it is just a stylish gadget for people like more the external view on a pc than performances which are as many others!!
on the sony vaio surely they are ok as pc but really expensive too!!So i think it depends from needs and configuration you want on your next pc!!
You also consider that between these 2 there are differences as regards the os so vaio normally are based on windows and macbook macos/leopard os so it depends from tastes too here!!