Windows failed to finish booting so it will go to that
screen until it does complete booting.
At that screen he has tried to boot to safe mode? If safe
mode also fails it tends to suggest either operating system
corruption, or hard drive failing.
You could get the hard drive manufacturer's diagnostic
utility from their respective website and make a boot floppy
or CD to test the hard drive. If it fails you might as well
think about RMA return if under warranty or buying a new
drive if not under warranty.
If it passes, or it is not viable to test the drive you
could always do a repair install of windows or format the
drive and do a clean install... if it came with or you can
acquire a windows installation disk. If it came only with a
restoration disk that too is an option.
The remaining question if you have to format and reinstall
is whether there is any valuable data on the drive. If so,
you could boot another OS like a Ubuntu LiveCD to access the
data in the same system and save it to a CD or USB
thumbdrive, or you could pull the drive out and mount in
another system, booting that second system's original
operating system/drive and acessing the drive in question to
copy data off.
I suppose there is also the possiblity of some kind of virus
infection, it is another reason to pull the drive, mount in
another system, and scan it.
There are other possiblities like general hardware failure
that makes the system generally instable enough to finish
booting windows, but less often is it seen in a case where
the system manages to get to the same point in the boot
process and that menu you reported, on a consistent basis.
Regardless you might pop the side off the system and inspect
it for fan failures, dust buildup, etc, especially if he's
in a climate where there has been signficant room
temperature increase as spring and summer approach in the
northern hemisphere.
