I think your problem is here (bottom of the list) --
Manufacturer NVIDIA
Model GeForce 8600 GT
GPU G84
Device ID 10DE-0402
Revision A2
Subvendor NVIDIA (10DE)
Series GeForce 8
Current Performance Level Level 0
Technology 80 nm
Die Size 169 mm²
Transistors 289 M
Release Date Apr 17, 2007
DirectX Support 10.0
DirectX Shader Model 4.0
OpenGL Support 3.0
Bus Interface PCI Express x16
GPU Clock 540 MHz
Memory Clock 700 MHz
Driver version 6.14.11.6371
BIOS Version 60.84.51.00.17
ROPs 8
Shaders 32 unified
Memory Type GDDR3
Memory 256 MB
256MB is only half the video RAM of what the game specs recommend.
That means the computer may be using system RAM to supplement the video RAM -- and you only have 2046 MB of that -- 2GB where the game's specs at
***Adventure Shop*** ask for 2.5 GB
BIOS: Phoenix ROM BIOS PLUS Version 1.10 2.5.3
Processor: Intel(R) Core(TM)2 CPU 6600 @ 2.40GHz (2 CPUs)
Memory: 2046MB RAM
Of course you're using XP instead of Vista, 7, or 8 so you
may not need a full 2.5 GB of RAM for the game in XP.
In the game settings it has:
Graphic Settings:
Fullscreen mode
Window size: 1920X1080
HD Cutscenes
Additional Effects:
High>MED>LOW
Are you able to reduce the windows size, set "Additional Effects" to LOW, and put Cutscenes on less than HD? If so, does it help at all? Maybe one or more of those changes would help with the slow loading and "sticky" mouse.