you have to go into your bios, to get into my bios, i press delete on the main screen before windows starts, depending on how old your computer is, and what type of mobo you have, it can be different, some people press F2 to get into bios i think.
well, i dsont know exatly how you would overclock your cpu/ram, but i can tell you how i did it.
Warning: dont overclock your ram if its cheap stuff, like generic ram like mine, this sort of generic ram that i have got can only handle up to 50mhz overclock, i am currently running my ram at 425mhz, the stock speed is 400mhz.
ProcalX has made some good posts, and thread on guids to overclock, i suggest you take a look at them.
also, if your motherboard is a standard intel motherboard, or an old motherboard, depending on the manufactuter, some motherboards dont include any overclocking options, but like with my intel 810i motherboard, i press a key, i think its F11, and it unlocks some overclocking options, but my cpu is locked.
anyway, what i did to overclock my AMD 64 3700+ is, to get it to 2.8ghz, decreased, the HT multiplyer to 3x, as if i left it at 4X or 5X, i would have to reset cmos, as it would make the HT (hyper transport) go over 2000mhz, and then this makes windows crash, if its done inside windows, or freeze upon starting your computer.
So i decreased the HT multiplyer to 3x, then in 5mhz increments, i upped the FSB, all the way from 200mhz, ot 254mhz, in order for me to stay stable at 2.8ghz, i had to upp the voltage from 1.4v to 1.45v, i alsa had to change the FSB Ratio to 1:1.6 so the ram frequency never went too high, as if i never changed the CPU/Memory ratio, i would end up frying my ram as it would have been running at 504mhz.
so, at the moment, my cpu is overclocked by 600mhz, i was able to be 80% stable at 2.9ghz, thats 700mhz overclocked, from 2.2ghz, but 3.0ghz, that made my bios all garbled, and i couldent boot into windows, i dont understand how it damaged my bios, i had to reset the cmos by shorting 2 pins on the motherboard.
i would have done a step by step, but i dont need to, procalx has done a very handy tutorial here:
http://www.hardwareforums.com/how-overlock-ongoing-tutorial-9373/
Also, by overclocking your cpu, you might not get that much better result sin games, what is your full system specs at the moment?
and all cpu's dont overclock well, so dont have your heart set on getting blazing fast result's.