I don't understand your problem. Your have Win7 loaded on your hardrive and your trying to install XP over the Win7 and it wont install?
Yes, sir thats why im asking whats the problem, ill attached here some info of my pc hope this can help you see/solve my problem,
NVIDIA System Info:
[Display]
Processor: Intel(R) Pentium(R) Dual CPU E2200 @ 2.20GHz (2200 MHz)
Operating System: Windows 7 Ultimate, 64-bit
DirectX version: 11.0
GPU processor: GeForce 8400 GS
Driver version: 196.21
CUDA Cores: 16
Memory interface: 64-bit
Total available graphics memory: 2047 MB
Dedicated video memory: 256 MB
System video memory: 0 MB
Shared system memory: 1791 MB
Video BIOS version: 60.84.6F.00.00
IRQ: 18
Bus: PCI Express x16
[Components]
nvCplUI.exe 2.8.290.13 NVIDIA Control Panel
nvWSS.dll 6.14.11.9621 NVIDIA Workstation Server
nvViTvS.dll 6.14.11.9621 NVIDIA Video Server
nvMoblS.dll 6.14.11.9621 NVIDIA Mobile Server
NVMCTRAY.DLL 8.17.11.9621 NVIDIA Media Center Library
nvDispS.dll 6.14.11.9621 NVIDIA Display Server
NVCPL.DLL 8.17.11.9621 NVIDIA Compatible Windows7 Display driver, Version 196.21
PhysX 09.09.1112 NVIDIA PhysX
NVCUDA.DLL 8.17.11.9621 NVIDIA CUDA 3.0.1 driver
nvGameS.dll 6.14.11.9621 NVIDIA 3D Settings Server