It is necessary to maintain the current system by installing the latest security updates.
On July 14, 2010, Microsoft Will stop providing security updates for Windows XP SP2 and earlier. Therefore it is essential to go to SP3 (Which Will be supported until April 2014).
Installion via Internet
Open Internet Explorer and go to http://windowsupdate.microsoft.com/
and follow the instructions.
Installation without Internet connection
To install SP3 Without internet connection, download the update on this page:
(About 324 MB)
You can put it on a USB key to update the PC with no internet connection.
AutoPatcher freeware that can download updates without installing them. Once Downloaded, They can be tranfered to a USB key.