Annual Computer Upgrade - Advice Appreciated

EDIT: Simplified my original post in hopes of getting (any) replies.

Current Machine
Pentium 4 2.4 GHz, 800M FSB
1.5GB PC3200
GeForce 4 6600GT 128MB (AGP)
West Digital 80GB, IDE hard drive
Creative 52x CD-ROM
AOpen 12x CD-RW burner
AOC Spectrum 9Glrs 19” CRT monitor
Windows XP Home

Proposed Purchases (all prices are Newegg & include shipping)
Athlon 64 X2 4000+ Brisbane…57.00
Asus M2A-VM…71.50
2GB Corsair XMS2 DDR2-800…33.00 (after rebate)
GeForce 8600GTS 256MB…86.00 (after rebate)
West Dig Caviar SE16 320GB SATA hard drive…75.00
Samsung 20x DVD burner…34.00
Acer AL2016WBbd Wide 20" LCD monitor…194.50

It’s time for my annual computer upgrade. Typically, I budget a firm $500 for this. This year, I need to upgrade my wife’s system to a PCIe capable one, so I’ve gone a bit over my usual maximum. My wife’s played WoW & Diablo 2 in the past, but has stuck to Bejeweled & Sudoku lately, so she doesn’t need a high-end graphics card.

Any recommendations for better bang-for-the-buck components would be appreciated, given my budget considerations. I plan to buy near the end of this week (end of Feb).

How did it go?

Components are still in transit; I’ll likely receive them tomorrow. Due to the overwhelming support (or condemnation, depending on your temperament) of the Qt3 hive-mind, I went with most of the components I listed. I found a slightly cheaper MSI motherboard, and a cheaper but less powerful videocard (Radeon HD 2600 Pro), knocking the total down to $515 after rebates.