What if my IP address has been the same for 4 months? It use to get changed every week or two with my cable connection. I have the DHCP service running in XP. In zone alarm I can see my isp trying to connect or something but being blocked. Is it worth changing IP address if it works anyways? Should I turn off DHCP then if its not retrieving an address?

If your ISP says to set your PC to obtain an IP automatically, that's what you should do. If you set a static IP and your ISP assigns that address to another customer, one or both of you will be unable to connect. DHCP servers usually try to assign an IP to the MAC address that last used it, so it really is not unusual to have the same address for months.

I'm thinking that you don't have ZoneAlarm running as a service, just at start up? Don't turn off the DHCP service. Every time you reboot your machine, it goes out and gets an address from your ISP, before ZoneAlarm starts up. It just happens to be the same address. Mine has been the same for months also, but my other machine's IP changes regularly (ie: when I hook it directly to the internet and not through my proxy). You should allow the Sevice and Controller app access through ZoneAlarm. If your lease expires on the IP address before your next reboot, your connection will die (until you reboot).

Changing IP address is not a solution if you are being bothered by the alerts being shown in your Zonealarm. It is possible that the IP block that is within your ISP's network is the IP address being used by their cache server. Meaning if you try to surf to a specific web and its in the cache server it sends a message which tells you that the website your trying to access is in the cache already. That's why it ends up in your Zonealarm alerts. FredF is right in saying IP addresses are mapped to a MAC address which is your Network Interface Card(NIC). It is possible that you can have the same IP for months because it remembers the last MAC address who used that IP address when you re-boot your PC. In addition to this, IP address leasing depends upon the setting of your ISP's DHCP. Lease expiration also refresh everytime you release/renew your IP or re-boot your PC.