those temps are fine and the vcore fluctuation is normal.

now, to burn in your system you can use any program that will stress your system or just use it as you would normally. you don't really need to burn it in, but if you plan to overclock, it might help you reach higher speeds.

i usually use prime95, superpi, 3dmark01, and memtest86+ to test my system's stability after overclocking, and to "burn it in" at that speed. i usually run prime95 and memtest86+ for at least a total of 10-15 hours to make sure my system is as stable as i want it. if you're going to run everything stock then there's no need to do anything other than use your computer. as for the arctic silver, after about 200 hours of use the thermal properties should be at its optimal level and you should notice a decrease in temps, but nothing major.