Ann Dunham replied:

So that leaves us with fleshing out:
1. Firewall
5. Router passwords

I really know almost nothing about firewalls, so I will let others flesh
this one out.

I will ask a few questions though, since WinXP doesn't come with a firewall
(and since routers always come with a firewall).

1. The first question is why we'd need a software firewall if the router
has a hardware firewall.

2. The second question will be WHICH free software firewall is the best one
for Windows XP.

I don't know software firewalls, but I know how to google:
https://www.google.com/search?q=best...tware+firewall

The problem, as always with noobs doing Google searches, is that it finds
too much.
http://www.techsupportalert.com/best...protection.htm
http://www.techradar.com/news/the-best-free-firewall
http://www.pcmag.com/article/313986/...free-firewalls
http://www.makeuseof.com/tag/free-fi...dows-compared/
http://www.askvg.com/top-5-best-free...e-for-windows/
https://www.geckoandfly.com/12087/5-...osoft-windows/
etc.

Skimming them for the venn diagram overlap, the following free firewalls
seem to be repeated the most in the articles.

ZoneAlarm
http://www.zonealarm.com/xp/
http://download.zonealarm.com/bin/fr...43_119_000.exe

Comodo
http://download.comodo.com/cis/downl...er_6113_c7.exe

My question is which one of those two to invest my efforts in?
Seems that ZoneAlarm is more often mentioned as the number one.
Is that correct?