Best/Ideal HD partitioning for a new WinXP Pro installation

I have always wondered what really gives out the best system performance when it comes to HD partitioning.
I have 4 Hard Disks in my rig?:

1TB 32MB Cache 7200RPM
1TB 32MB Cache 7200RPM
512GB 16MB Cache 7200RPM
512GB 16MB Cache 7200RPM

2 x Barracuda 7200.11 SATA 3Gb/s 1-TB Hard Drive (32MB Cache)
http://www.seagate.com/ww/v/index.js...&reqPage=Model

1 x Barracuda 7200.10 SATA 3.0Gb/s 500-GB Hard (16MB Cache)
Drivehttp://www.seagate.com/ww/v/index.jsp?vgnextoid=b9df99f4fa74c010VgnVCM100000dd04090aRCRD

1 x Barracuda 7200.9 SATA 500-GB Hard Drive (16 MB Cache)
http://www.seagate.com/ww/v/index.js...00dd04090aRCRD

I’m going to do a fresh WinXP Pro installation and I was thinking of dividing the 1TB HD to 3 partitions:
C: WinXP Pro (20GB), Linux (15GB) (Dual Boot)
D: Games installation / execution (100GB)
E: Backup / Downloads (880GB)

And use the rest 3 HD as they are (Unpartitioned)
1TB, 512GB & 512GB for Backup / Downloads.

Or should I use the entire 1TB HD for WinXP, the 2nd HD 512GB for games installation, and the rest: 1TB & 512GB for Linux & Backup / Downloads.

Any opinions / suggestions will be highly appreciated.
Thanks in advance.