Can't shut down

Dear all:

I'm using WinXP Home and I'm having problem shutting down the box. It functioned properly at the beginning but after awhile, I might accidentally deleted some programs (or due to other causes) so now whenever I try to shutdown, it keeps restarting instead. And when it does, these 2 message boxes pop up:

I'm using a Chinese OS so I don't know the exact wording of the message boxes but their approximate meaning are

1. "shell32.dll, Control_RunDLL C:\WINDOWS\System32\main.cpl," error

2. "C:\WINDOWS\DOWNLO~1\CnsMin.dll" not found

Would someone pls tell me what I should do to make it shutdown instead of restart?

Thanks in advance!