You do not need to buy Office if what you have fits your requirements.
In any case if you find only Office will do, because you are sending and/or receiving Office files to be accessed on other computers, OpenOffice is free, downloadable and fully compatible.
I thoroughly dislike Norton and believe it slows the computer by hogging too many resources.
I recommend a firewall - ZoneAlarm or Comodo
An anti-virus - AVG or Avast
Anti spyware - AdAware AND AVG antispyware (used to be called Ewido).
All are free, and all can be safely downloaded from here:
http://tinyurl.com/y83v23
Except Comodo, downloadable here:
http://tinyurl.com/la95f
I admire you for getting to grips with Vista.
By the way - OpenOffice downloadable here:
http://tinyurl.com/f4t79
Although if your laptop has come with Microsoft Works, the word processor is now fully compatible with Office Word.
If you do decide to remove Norton, let us know and we will guide you through it.