Perhaps you can get away without formatting and re-installing if you just run some maintenance on the machine, and have a look at this program, or use that later.
Dell De-Crapifier
FAQ779-4784 may help.
windows XP running very slow
thread779-796508
As to formatting and clean installing that may depend on what media Dell has supplied you, whether it is only a recovery partition, or recovery CD to restore to factory release condition. The answers should be in any supplied manual or found on the Dell web site.
reinstalling xp & saving info
thread779-1313351
How do I use the Dell™ PC Restore by Symantec Utility?
Your first link seems to be speaking about formatting floppy disks and will not be much use to you.
The second link seems more appropriate, but again most of these examples are using retail media such as the retail XP CD, and not recovery media.
You will have to make the laptop boot from CD either via options in the Bios, or check with Dell to see if you start the whole recovery procedure some other way, for example by pressing the CTRL + F11 keys at boot. Do check with Dell.