Some Dell systems also have a hidden partition or file for restoring your computer back to factory installation, without the need for the recovery discs... They still included the recovery discs though, in case you wanted to free up some space...
IIRC, my Dell at my former company, running Windows 98 and FAT16/FAT32, was setup this way-- in the root directory of the main drive (i.e. c:\) were a couple hidden .bat files. I believe one was called zztop.bat. I'm not sure if the newer systems with XP on them have this, as most recovery discs are on CD/DVD these days, instead of both...
To check for this, do the following, or use Explorer and set your view to see all hidden/system files:
Click Start-->Run
type CMD and press enter
at the command prompt, type C: and press enter to ensure you are on the main drive (usually C:)
type CD \ and press enter
type DIR /a and look for zztop.bat
Newer systems may have another hidden recovery tool/partition with a different name...