Don't know how Dell works, but I have an HP with Vista Home Premium.
Instead of a disc supplied by the manufacturer, your disk should be
partitioned into a C: and a D:. The D: drive should also have system
saved files on it. If you know the DATE that 'no .exe' happened, then it
might be simple for you. If not, you'll either have to edit the the
registery or completely rebuild the C: drive.
Try this, when you first boot up the system, you should have which
Function key to press to do a system recovery. On mine it's F11. Keep
pressing it until you get the recovery screen. Then on the screen select
ADVANCED. It should show you a list of files you can recover. Select the
one that dates BEFORE you know the 'no .exe' error occured and let the
system do it's thing. The great part of the ADVANCED option is it will
restore the system files to that date and ONLY the system files. Any of
your regular files will not be changed. It takes about 15 minutes and
saves you a hole lot of work. This option has saved my butt many times.
It's worth a try.