Failure to Power Off at Shutdown

8 times out of 10 after I select Shut Down using Windows 98 SE on my Dell xps 1000r, the shut down does not get past the "Windows is shutting down" screen. I have to manually shut off the pc by holding in the "start" button.
On the next start up there is NO "scan for shutting down improperly"
What do I need to change in my msconfig to achieve a normal shutdown?

Thanks,

dicmcrae in Philomath, OR