before you try overclocking you need to understand that overclocking is the practice of running components at higher clock speeds than they were intended to run. if done right, it can yield significant performance gains with minimal cost to the user. if done wrong, overclocking can ruin parts and cause instability. you said you'v got no idea what you're doing, so if i was you i would think twice about trying overclocking without any prior knowledge. successful overclocking takes knowledge and experience.
with that out of the way...
your motherboard uses the via M266 chipset. this chipset uses the front side bus of your cpu (fsb) as a standard system speed. increasing your fsb to overclock will make your pci slots, agp slot, and hard drive interfaces run faster:
a modest 5% overclock of your cpu would make other critical parts of your computer overclocked too. the video card, pci cards, and hard drive interface would speed up as well. let's say your video card can take the extra speed (or your integrated one can too as it will also be sped up) and your increased pci clocks cause no problems. what's going to get you is the increased ata hard drive interface. ata interfaces are generally suspectible to faults whilst being overclocked. unlike when other components encounter errors (the machine will blue screen or reboot), the hard drive controller can and will actually write corrupted data to the disk. this can easily corrupt an entire hard drive and force you to reformat it to regain access. besides that, increasing the fsb will negatively effect your memory timings and reliability.
as you can see, overclocking would be a bad choice for you because you haven't the knowledge/experience and your motherboard will not yield satisfactory results. the only other way you can overclock, by changin the multiplier, is impossible because intel cpus have locked multiplier settings. the nforce motherboards, on the other hand, allow the fsb to be altered without effect on the other buses. the bottom line is: you haven't the chipset for it.
i hope this information helps you and all others who read it.