Thermal Paste Questions/Good thermal pastes?

Hardware Hub CPU
1

is it nescesarry to apply all over the CPU? or only the center and let the Heatsink push it down? How much is needed?

also what is a good brand of thermal paste?
so far i've found IC essential e1 thermal paste coolermaster at my local computer accesory shop. Is it good? 

2

http://www.youtube.com/watch?v=-hNgFNH7zhQ&feature=plcp

3

good brand of thermal paste? i'm using ic essential e1

4

Arctic Silver 5

 

http://www.newegg.com/Product/Product.aspx?Item=N82E16835100007

5

http://www.maximumpc.com/article/features/geek_tested_17_thermal_pastes_face

6

MX-4