I have cable, and depending on what you dad means by "filters" (does he mean filters that prevent you from going to bad sites, or filters that prevent hackers/viruses from coming to your computer? [which is called a firewall])
The problem with DSL/Cable is that once you turn on your computer...you are ALWAYS on. Which leaves an open gateway to Hackers, Viruses, and Spyware to just waltz right in and make their home on your computer. The solution (which I suggest EVERY computer gets that has DSL/Cable) is to purchase a firewall program that prevents other people on the internet from having access to your computer.
I suggest a Firewall called "
Zone Alarm Pro."It costs $39.99 and you have to renew the subscription every year...but IT'S WORTH IT. Of course, Windows XP comes with their own Firewall, but its VERY easy to get by...
Let me tell you a story, we have 3 computers at our hows (2 laptops and 1 desktop) and 2 of them have Zone Alarm Pro...The other is owned by my brother who only wants to invest in his Car and Video Games for his computer (forgets that a good Firewall is a good investment in keeping his computer running) Well His laptop is "supposedly" faster than the Desktop (more Ghz, More RAM, more everything)...except it lags SO BAD during any online game... Well, we ran a free
Pest Patrol and he had OVER 100 Spyware Cookies bogging down his computer... My laptop had none, and the Desktop also had none... So Zonealarm (cooperating with Pest Patrol) prevents ANY viruses, hackers, or Spyware from getting on the computer...
A good Web filter is called
Cybersitter if they are worried about you going to bad sites...
It seems to me that your parents are...errr... "economical" at best, so it's going to be tough trying to persuade them to go DSL/Cable and getting them to purchase Zone Alarm Pro, Pest Patrol and Cybersitter... but it is always worth a try...