I know that a Dell XPS600 (Pent D 840 (3.2Ghz) with 2GB of RAM) is quite laughable by many of your standards. I currently have this machine as an extra rig with a nVidia 8600GT on XP 32-bit. The 8600GT is not doing well, at all, in Lost Planet, even @ 1024x768...pretty bad stuttering.
However, I also have a 8800GTX in my Vista rig (described in my sig). I'm considering moving the GTX to the Dell to see if it would give me a fluid experience @ 1280x1024. Is this a waste of time because the yesteryear processor is going to bottleneck to the point that it may not be usable or could this be a promising endeavor in your opinion. The Vista rig is not doing well in Lost Planet...doesn't start often, and now, I can't save after killing one of those dreadful bugs.
When it does start I can game @ 1920x1200 or 2560x1600 (so, its okay when it is actually working) ...could be the rig, could be the game, but I wanted to try LP on another machine, ...but wanted to get opinions on whether or not its just a waste of time to put the GTX next to a Pent D 840 hoping for descent fps @ 1280x1024.
That Pentium D is going to bottleneck your Vid Card. When I got my 8800 GTS 640, I still had a Pentium D, and the performance was sad. It was barely better than my 7900 series. Upped the processor / mobo and the experience was phenomenal. So I guess - yeah, you will experience some gain in FPS, but I don't think it will be a mind-blowing experience.
No need to uninstall your apps.Use FSAutoStart,it will shut down all programs not needed to play automatically and when you are done and exit the game it will reload everything for you.Best of all its free.