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SplitFinity, TTSG, Vivid Video, WebPower, Whitehorn Ventures
These are all sites that (in my observation and opinion only) host mostly or exclusively adult matter, or host or advertise via spam. In any case, they are generally not appropriate for families with young children or for corporate users.

Filter Scanregw hacks
This might sound scary, but here's the deal: one day I caught Scanregw (that's the Windows registry checker) supposedly contacting IPs in this range. This was back in the days when I used Zone Alarm. In retrospect, it was probably ZA going nuts (as it often does) but I've blocked these anyway. Take 'em or leave 'em if you want.

Permit ICMP
This allows Internet Control Messaging Protocol out. It's a complement to the ICMP In and ICMP Block rules at the beginning of the rule list.
Basically, this allows your computer to send out any kind of ICMP it wants or needs to (for example, to tell a website you're visiting that it's sending data faster than your computer can handle it.)

Permit Localhost Resolution
A duplicate of the rule on the first explanation page, this is used to log traffic. It's actually normally disabled, but you can enable it if you want.

Eudora
This rule is used to permit the Eudora email software to talk to the net. If you don't use Eudora, disable or delete this rule.
Ideally, you should modify this rule so that the only IP address ("Remote Endpoint") it is allowed to talk to is that of your ISP's email server. Your ISP may be able to help you with this. It also is only allowed to access the net on cerain ports needed for email services. The only ones that are really important to email are: 25 - SMTP (for sending email) 110 - POP (for reading email). 113 - Authenticate (sometimes needed to "log in" to your ISP's email server.

Outlook Express Out
Like the Eudora rule above, this rule allows Outlook Express, the email program that comes with Windows, to talk to the net. Again, if you don't use it, delete the rule. This rule restricts it to certain ports so it is better behaved. Also, ideally, you would want to find out the IP address of your ISP's email server and Edit the rule, putting that in your Remote Endpoint field (single IP).
Outlook is one of the most heavily exploited programs in existence, probably second only to Internet Explorer. While it is strongly advisable that you use something else, if you must use it, this rule will keep it more well-behaved.

Microsoft Internet Explorer Out and In
This pair of rules allows Internet Explorer to access the net. If you don't use IE, or don't use it regularly, delete or disable these two rules. As is discussed on several parts of this site, it is probably the single biggest privacy and security vulnerability on your system.
It is set up so that, if you must use it, that it will only be allowed to talk on certain ports, keeping it better behaved. Specifically, they are:

21 - FTP (for transferring files via FTP)
25 - SMTP (sending email, this is actually because Outlook can work through IE)
80 - HTTP (for normal Web browsing)
110 - POP (for reading email through Outlook)
113 - Authentication (for logging into certain sites and email services)
443 - SSL (for encrypted communications, usually used with online shopping)
8080 - HTTP2 (alternate port for Web browsing)

The Microsoft Internet Explorer In rule exists so files being downloaded via FTP can be sent into your computer.

Mozilla Out and In
This rule is used to permit those of you with the Mozilla browser to allow it to talk to the net. If you don't use Mozilla, delete these two rules.
Mozilla is widely considered to be an inherently much safer browser than Internet Explorer. Still, a malicious program could always hijack it, so, like with Internet Explorer, it's restricted to talking only on certain ports. That's good form, you know.
Because Mozilla also has built-in email and news software, it is allowed to use the ports appropriate to those activities. Here's a list of all of them:

21 - FTP (for transferring files via FTP)
25 - SMTP (sending email, this is actually because Outlook can work through IE)
80 - HTTP (for normal Web browsing)
110 - POP (for reading email through Outlook)
113 - Authentication (for logging into certain sites and email services)
119 - NNTP (for reading and posting to newsgroups)
443 - SSL (for encrypted communications, usually used with online shopping)
8080 - HTTP2 (alternate port for Web browsing)

The Mozilla In rule is there so files being downloaded via FTP can be sent into your computer.

Proxomitron Out and In
This allows Proxomitron to talk to the net. Like with all the browser- and email-related rules, if you don't use this, disable or delete the rules. Proxomitron is allowed to talk on HTTP ports (for viewing normal webpages), FTP (for filtering FTP sites) and on email ports, to filter out some of the junk that often comes in email like web bugs, cookies, unwanted and inappropriate images, etc.

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