I second that last statement. However if it helps and you have access to a reasonable internet connection and a dvd burner .
Try Ubuntu. It works well even on older pc's.
It is not known for getting viruses.
And you can try before you install it . It allows you to boot from the dvd and run a live session.
I had it years ago on an old vista laptop. From then until Vista SP2 and finally 7 came out did I go back to windows.
However I do do the odd bit of tea n sympathy.
So if you need a little advice feel free to pm me.
Il see if I can help.
IT is my business so hopefully I can help.
But it is vital you change from XP soon
You will be unprotected from anything.
Id bet on a surge in serious consequences from everyone from someone such ad your self right up to high ticket sites where the mind set is. If it aint broke.....
Windows XP while very good has been supassed.
But the final nugget of advice.
Never but ever try Windows 8.1 it is the mosy cynical half thought through over complex and many other things that I cant type here.
For the average user . Their world would end!.
Regards
Jon