>has nybody had this problem ? When I use VFP (especially help), it freeze my pc after 5-10 min(less than that when I use help).

Are you installing VFP6? Are you also installing SP3? Make sure these have installed error free before troubleshooting.

I haven't heard of this problem. Some things to try:
- uninstall VFP and MSDN then ensure system does not crash with other apps
- reinstall both again, test for freezing problem

If problem persists:
- trying setting video driver to a standard vga

I am starting to run out of ideas at this point you could try installing VFP on another computer to see if it runs better or considering reinstalling Windows to ensure it is okay.

I am sure others will have more suggestions.