The easiest way to use the RSS feed on PB is to get the free Firefox browser (
www.firefox.com). Then go to PB and in the address bar at the far right side you'll see a little orange and white box. Click on that, click "OK" and you'll be subscribed to the PB RSS feed. There'll be a PB item just below the address bar and you can click on that and see the titles of the latest posts. If you want to go there, you just click on that item.
I believe Internet Explorer has something similar in its latest version, but because many viruses and worms exploit weaknesses in IE, I think it's better to use Firefox.