That's ridiculous advice...here's why:
TIF, cookies and temporary files have no impact on a computer's speed,
unless the hard disk is almost completely full. If that were true, the OP
would have the same problem before installing SP 2, and probably would not
have been able to install the service pack (which checks for available disk
space before installing.)
Installing SP 2 does not cause disk errors, nor does the installation add
items to startup that would cause the system to slow.
This and other inane advice contained in the fixyourwindows.com web site
make it at best a waste of time and at worst detrimental to a Windows PC.
Ted Zieglar