computer restarts into black start up options screen

[malibumom]

Ok, about two weeks ago my computer started up normally, crashed in a matter
of minutes and then the black screen with the start up options comes up.
After many attempts to start in safe mode, last known good configuration or
normally, each time with the computer crashing and restarting always coming
to the black screen.
I have no idea what makes it finally boot but once it does it seems to be
okay until it is shut down and then turned back on.

If I choose the safe mode a list of different drivers comes up. Sometimes it
restarts over and over again and sometimes it freezes. If I try start
normally, it will restart over and over and then I get the message that the
file WINDOWS\system32\ntoskrnl.exe is missing or corrupt.

I have been having problems with the automatic updates but was able to get
it to work two days ago and installed a critical Net 3.5 update. Yesterday it
started up perfectly and there was no problem the whole day. This morning,
back to the same.

I don't have a WINDOWS XP CD as the system was pre-installed. The recovery
CD I have won't start the computer, even though I set the BIOS for a boot
from CD.

Any ideas?

 

[malibumom]

I should add that once it starts and I get the "this system has recovered
from a serious" box, when I send it says that it is a device driver. I looked
in the device manager in the system info. One device, a multimedia audio
controller has an exclamation point. When I right click on it, it says the
device is not working because the driver is not installed. The problem with
this is that my computer is a bit of a frankenstein and I have no ideal who
the manufacturer is or how to find a driver to install. In the properties
screen all it says is unknown. I don't know if this is related but that is
one other thing going on.