Microsoft has a comprehensive page on this subject here:
http://www.microsoft.com/windowsxp/sp2/sp2_whattoknow.mspx
The install is not complicated, but it may take 15-30  minutes depending on
your computer and the updates it needs.
When it's done, you'll find a new "Security Center", which is just a
firewall, popup blocker in IE, and other, less obvious security
enhancements.
I've installed this update on 2 Dells without any difficulty, but it would
be wise to backup your data first.
Go for it.
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 Hello; I was recently notified by Dell I should update windows XP home
edition with SP2- it sounds complicated and should I do it> I understand it
protects me from invasion by sounds confusing to me.

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