new user trying to update windowsXP

i just unpacked my new ApsireOne 1635 8.9 netbook and went through startup pretty well. Got on-line and tried to do a windows update several times with no luck. I go to start progarms...windows update and then the computer tries to get the site but it keeps saying it can't log onto the site. I have been able to get to other sites so i know that i my connectivity is working. I also had the computer run through a test that it offered to do and then it rebooted and we tried (unsuccessfully) again. So, i have shut things down because i worry about not have XP updates especially for security reasons. Is there a new website for updates or is there something else that i am not doing correctly?/

I'd also like to get rid of McKafee antiviral and put in the AVG program, but not sure which i should do first (remove McKafee or install AVG first).
Let's just say that i am a very fundamental type of user and hesitate to do anything when i am uncertain.

 

Your problem with update can be related to setting of AV (but I am not saying you should be using internet without any AV). Being you the first thing I would do was uninstalling MacAffee and putting in a different AV sofware. AVG or avast are good choices. Then you will see if you problem persists. REM: in no case you should be installing a new AV software without uninstalling the old one, Some softwares would even not let you to do so.