You didn't say, but I am guessing that you have an E5200 series chip.
Generally, what Moto suggests is the easier way because you reduce the effects of instability on the memory system.
That is the approach I take.
GA-EP45-UD3P | Q9550 OC'd to 3.6 GHz (425 MHz X 8.5) C3 stepping
GA-EP45-UD3L | Q6600 OC'd to 3.6 GHz (400 MHz X 9)
GA-EP35-DS3P | E7500 OC'd to 4.1 GHz (373 MHz X 11)
GA-G41M-ES2L | E6500 OC'd to 3.87 GHz (352 MHz X 11) FSB limited by G41
(I like Core2 CPU's and Gigabyte motherboards.)
Theoretically, the higher FSB freq X lower mult is better. In reality, for a given core speed, particularly with the Core2 CPU's, performance does not scale linearly with FSB freq. That is a fancy way of saying that performance at the higher FSB speed will not be 12% better.
Assuming that you do have an E5200 series chip, things are a little different because of the lower 200 MHz FSB freq. There's less stress on the memory.
Your core temps seem to indicate that you are using the stock cooler. Even a mediocre aftermarket cooler will help a lot because a dual core chip is much easier to cool than a quad.
You need to keep the load temps when running something like Prime95 under 70 C.
The E5200 chips are pretty good overclockers. With good cooling, many will reach 4 GHz. Mine unfortunately only goes to 3.87 GHz.
BTW, it's a coincidence that my E6500 does that in a G41 board.