Best Intel Core 2 Duo $100-200

First, I apologize if this is a common question. I browsed around but did not find a close enough match, and I want to get this build right.

I know virtually nothing about Intel Core 2 processors (used to be an AMD guy). All the different models are pretty confusing, especially when I find one with a higher product number and seemingly better specs that's priced cheaper than the next. All seem to be good overclockers.

So what's the best choice for value/performance/overclockability to hold me off until quad-cores become more mainstream, and what would be a good motherboard (non-SLI) to go along with it? I'm not necessarily interested in stretching the limits, as I'd rather achieve a respectable and stable OC. Cooling is built into the budget... so I don't need a $100 chip with a $80 fan/HS unless it's really the best choice for $180 total. I can go a little higher than $200 (USD) if warranted.

Also... is "Crucial Ballistix 2GB (2 x 1GB) 240-Pin DDR2 SDRAM DDR2 800 (PC2 6400) (4-4-4-12)" - good enough for such a build? Thanks!