I was saying that you wouldn't have ended up with a better deal at newegg since FRYs had the rebate offer going. Plus that was only value ram not knowing if you caught a deal on performance memory.
I run strictly WD drives here and had noticed the 640gb model when first seen. I was considering adding one or two 750gb drives to create a large storage array but ended up simply going for a smaller external drive to allow transferring a large amount of files between systems. After partitioning that should give you right up close to 600gb available while a 500gb model will see 465gb.
11gb even for XP is rather cramped especially if you plan to run any number of programs. Softwares will chew drive space as well as any amount of files like mp3s or video files you want to have onhand.
A good 80gb primary or even larger with a second storage partition works for most if you plan to split the drive. Vista presently shares one drive with a Linus distro while XP sees a full 465gb single primary for working with video which eats drive space right up.