As an alternative...
I believe that you can use EasyBCD to repair an XP bootloader, but I would think that the closer you hue to original XP tools in this case the better.
Google has told me that since Smartboot loads before any MBR, any attempt to repair the MBR before dealing with Smartboot is likely to make things worse.
It appears that there is a CD that can be used with a special key to restore Safeboot. You or the IT department should perhaps be in touch with McAfee for help and instructions. Google also mentions that if a backup of this Smartboot installation was made, it will fix the problem. Was whoever did the installation so thorough?
Might I strongly suggest that you make a cloned copy of the HDD using either Clonezilla or the linux command "dd". I don't think that you can make any misstep with this problem without getting in deeper trouble. A clone will let you try, then try again from the same point, if not a better one, then one none the worse