I think Rodry87 means that the OP should check the display settings outside LFS.
For Aleksander's school PC going by the GFX chipset, you can access the important settings via the CCC or right click desktop choose properties, click the settings tab, then click advanced.
Slide the 3D Performance slider between performance and quality, self explanitory
Always check the troubleshooting tab as hardware settings may have been reduced here.
Because its a school PC there could be hidden keylogging type software running, or other background processes, do you play LFS via vista or xp, I guess by your post you dual boot?
Maybe this laptop is just too full of stuff?
how many icons in your taskbar nr the clock?
How many processes running in task manager?