still using xp need help upgrading

Ok here is my dilemma i am currently using xp. going to overhaul comp and build a new one my question is the following:
1. intel 2.93 Dual Core or 2.33 Quad core
2. Is Ram going to make a huge difference is 1066 ddr2 5-5-5-15 or 800 4-4-4-12 ddr2
or should i just go with ddr3 but the cheapest i can find are 9-9-9-24

im building this for my mom i dont want it to need an upgrade for a while! and i know more and more software is utilizing the more cores but is the extra $50-150 worth it. i just want it to run flawlessly. here are links to everything i was planning on choosing from if more is needed like case and graphics let me know.
RAM: DDR2 Newegg.com - G.SKILL 4GB (2 x 2GB) 240-Pin DDR2 SDRAM DDR2 1066 (PC2 8500) Dual Channel Kit Desktop Memory Model F2-8500CL5D-4GBPK - Desktop Memory
DDR2 800 Newegg.com - G.SKILL HK 4GB (2 x 2GB) 240-Pin DDR2 SDRAM DDR2 800 (PC2 6400) Dual Channel Kit Desktop Memory Model F2-6400CL4D-4GBHK - Desktop Memory
DDR3 Newegg.com - G.SKILL 4GB (2 x 2GB) 240-Pin DDR3 SDRAM DDR3 1333 (PC3 10666) Dual Channel Kit Desktop Memory Model F3-10666CL9D-4GBPK - Desktop Memory
CPU QUAD: Newegg.com - Intel Core 2 Quad Q8200 2.33GHz 4MB L2 Cache LGA 775 95W Quad-Core Processor - Processors - Desktops
Newegg.com - Intel Core 2 Quad Q8400 Yorkfield 2.66GHz 4MB L2 Cache LGA 775 95W Quad-Core Processor - Processors - Desktops
DUAL: Newegg.com - Intel Pentium E6300 Wolfdale 2.8GHz 2MB L2 Cache LGA 775 65W Dual-Core Processor - Processors - Desktops
Newegg.com - Intel Pentium E6300 Wolfdale 2.8GHz 2MB L2 Cache LGA 775 65W Dual-Core Processor - Processors - Desktops

Whats your budget? I'd go with the Quad and DDR3, but that could be a bit more than you can spend.

Mom will be set for a little while with a rig like that. At least 2-3 years, I would imagine.

What is she going to do with it? Unless your Mom is going to be a power user / advanced gamer, I wouldn't worry about DDR3 or a quad. Pointless overkill. Go to Newegg and buy any basic combo and be happy. Win7 does not have massive hardware requirements.

Again i just want to emphasize that i want it to run flawlessly with all the windows 7 addons with no hiccups at all and will the ddr2 and dual core give me that?... thanks again

The DDR2 Ram and a dual core CPU will be fine like another poster said if your mom is going to surf and do a little E-Mail it will be fine she does not need the most current bleeding edge hardware.

addons - i may be wrong but im pretty sure windows 7 uses 3d applications which makes it look all nice and sleek. i don't want any lag or slowing down and im just not sure if core duo with the ddr2 would work "flawlessly". yes all she does is surf the web and email but she might wanna do a bit of light photo editing. i just like the nice extra's that it has and don't want to have to disable anything. actually if there is extra stuff i would like to be able to use it without having to worry about if my comp can handle it.... really leaning toward the cheaper stuff just need to verify im making a good choice.

The 3D stuff would be more dependent on the video most budget boards anymore have pretty decent onboard video even some with combo DVI and VGA outputs so save some money on the RAM and CPU and make sure you get decent video.

what motherboard are you looking to use?

Newegg.com - MSI N220GT-MD1G GeForce GT 220 1GB 128-bit GDDR2 PCI Express 2.0 x16 HDCP Ready Video Card - Desktop Graphics / Video Cards

Newegg.com - GIGABYTE GA-EP43-UD3L LGA 775 Intel P43 ATX Intel Motherboard - Intel Motherboards

http://www.newegg.com/Product/Produc...82E16819115056

Newegg.com - G.SKILL 4GB (2 x 2GB) 240-Pin DDR2 SDRAM DDR2 1066 (PC2 8500) Dual Channel Kit Desktop Memory Model F2-8500CL5D-4GBPK - Desktop Memory

Newegg.com - Antec earthwatts EA500 500W Continuous Power ATX12V v2.0 SLI Certified CrossFire Ready 80 PLUS Certified Active PFC "Compatible with Core i7/Core i5" Power Supply - Power Supplies

Newegg.com - Antec Nine Hundred Black Steel ATX Mid Tower Computer Case - Computer Cases

this is everything im thinking of buying, will it "FLAWLESSLY" (sorry it's my word of the day) run windows 7 ultimate? and even some decent gaming if i get bored? i mean do everything windows 7 is about and more? and last for at least 3-5 years?