TCCD, not TDDC, but I nitpick.
You have a great mobo/CPU combo for overclocking. What I would advise for the RAM, however, is getting the highest rated sticks you can afford/justify. Samsung TCCD's are awesome on A64 platforms with the tighter than tight timings. On a P4C setup, however, I want the guaranteed headroom that PC3700 or above gives.
Now, if you think you might upgrade to an A64 setup in the not too distant future, stick with your original plan. Otherwise, see if you can squeeze a pair of PC4000 sticks into the budget and have a ball. The TCCDs will still overclock if you've got your mind made up though.