Tasks : 1. Surfing Web
2. Watching You Tube
3. Playing online Flash Games
4. PC Gaming one Medium Setting, @ 1024 by 768
5. Want CPU Processing Capabilities
6. Want a Future Proof System (Will be using the system for 4+ Years
I would recommend a strong quad core, like a i5 "Haswell", or an 8 core FX8350 that excels in multi-threaded applications. While either of these choices will be more than you need today, getting more power now will allow the system to last the four years you want.