I’ve always had good luck with Zonealarm free version on Windows XP Home Ed.
Go to Zonelabs.com, scroll down to bottom right of webpage to download & install free vers.
Once installed, it will have to be ‘tought’ about your frequented websites.
With it running in the background, surf like normal, & you’ll get a pop-up box asking if Zonealarm should allow this.
Check the ‘Remember this’ BEFORE you click allow, or it will ask you everytime you go to your usual websites.
After you’ve ‘trained’ it (only happens in the beginning), you’ll only get the permissions pop-up occcasionally.
It may sound inconvenient, but it’s quite painless.
Also, Zonealarm will notify you when it needs updating. (eg., If you open the control center by double-clicking on the system tray icon, it will say ‘Firewall is up to date.’)
There’s even a quick tutorial that comes with it.
I never been hacked, and I’ve used it for 8 yrs.
It’s free & one of the best out there.