Help with Zotac 630i motherboard, and Intel E5200 CPU. Optimization or OC Help

Let me preface this by apologizing for the double post. I posted this exact same message in the Overclocking Motherboards forum, but it didn't look like many people went there, nor anytime recently. Plus I dunno whether this belongs in CPU OC, or Motherboard OC.

I'm kind of at a loss here as to overclocking, or AT LEAST optimizing my rig. I have an Intel E5200 CPU, and a Zotac nForce 630i motherboard with the GeForce 7100 built in, although I'm not using that, I have a Gigabyte Radeon HD4670 video card.
I also have 2 gigs of Corsair PC2 6400 DDR2 800 RAM, model # is TWIN2X2048-6400C4. Supposed to be rated at 4-4-4-12 at 2.1v

Anyway, I'm really confused at to whether or not my system is at it's optimal settings, and whether or not it can even be overclocked. All I see is how easy it is to overclock an E5200, but I'm not sure if my motherboard will allow it. My BIOS seems to be a lot different than the guides that I've been reading. Like I don't even see a voltage control in my BIOS except for one for NB voltage control.

I can adjust the speed of the FSB, although it says it's linked with the memory, which apparently can be unlinked as well. I can set the speed of the FSB, or the Memory. I can't seem to change the multiple of 12.5 anywhere, and I'm not sure that I'd want to. I can also change that FSB to memory ratio setting.

I'm partly confused by the memory speeds as well. I have that CPU-Z program now, as well as RealTemp, and that Intel Burn In tester, although I haven't really used that burn in test until I actually get some work done here.

If I'm overclocking my FSB, and CPU, I am NOT supposed to have the memory speeds over 800Mhz no matter what?
In CPU-Z it says the DRAM frequency is running at 400Mhz, and the FSB:DRAM is 1:2 is that right?

Also, should I change the command rate from 2T to 1T? I'm not sure if my memory can do that. I just know the website said 4-4-4-12, but my previous BIOS settings were higher than that, like 5-5-5-18. I at least changed that much so far, and the system runs fine.

I'm gonna stop here, and see what you guys have to say. I'm just really confused, and I feel like I shouldn't be. I'm thinking I can only go so far with this motherboard, unless there's some settings in it that cover the settings in other guides for other motherboards. Maybe this motherboard is more advanced than I think, although I highly doubt it.