To get into the Windows 2000 / XP Safe mode, as the computer is
booting press and hold your "F8 Key" which should bring up the "Windows Advanced
Options Menu" as shown below. Use your arrow keys
to "Safe Mode" and press your Enter key.
With some computers if you press and hold a key as the
computer is booting you will get a stuck key message. If this occurs, instead of
pressing and holding the "F8 key", tap the "F8 key" continuously until you get
the startup menu.
Trouble Getting into Windows 2000 or Windows XP Safe mode
If after several attempts you are unable to get into Windows 2000 or Windows XP
Safe Mode as the computer is booting into Windows, turn off your computer. When
the computer is turned on the next time Windows should notice that the computer
did not successfully boot and give you the Safe Mode screen.
I would suggest that you run only one stick of Ram at a time to determine if they are the problem.. Also these CPU's had heat problems that damaged the cpu. This also causes freezing. I would consider resetting the CPU and the heat sink, and case fans are clean and working.