Do you do much overclocking? You could get an Intel quad CPU for the same price like a Q6600 and OC it over 3GHz for example. P45 chipset boards are obtainable for under $100.
Is there a reason why you want to go with AMD? If you just like AMD and want to support them then that is perfectly fine but if you go with Intel you can get a better performing gaming system with better overclocking potential.
How much do you want to spend? There are different versions and prices of the components that you listed so I am curious what you plan to spend.
Is your old RAM generic or something? Is it three 1GB modules? You will want to be running in dual channel and three 1GB modules won't let you do that. DDR2 800 is so cheap right now. You can get 2x2GB for under $30 with a MIR and clock it up to 1066. I wouldn't pay for 1066 RAM. http://www.newegg.com/Product/Product.aspx?Item=N82E168...
If you don't like MIR, the G.Skill 4GB set is $39 flat.
Are you building from scratch or replacing components in your old computer? Curious about what you are doing for a PSU.