Your router is assigning your systems internal IP (starting with 192.168.xxx.xxx). The WAN IP (the IP that your ISP Assigns) is what is shown when you goto whatsmyip.net. To find the internal IP, in XP, do:
1. Start > Run > type "cmd" (w/o quotes) and hit enter
2. type "ipconfig /all" (w/o quotes) and hit enter
3. look where it says "IP ADDRESS" and starts with a 192.
now, you cannot enter the "192" IP and access the machines outside your network. You'll need to use the WAN IP which is the IP taht whatsmyip.net assigns.
if you want to use pcanywhere from outside the lan (eg. work) to access files inside the lan (eg. pc x in your homenetwork), you need to use "Port Forwarding" . almost all routers come with this features.
1. first find the port pcanywhere uses. you can use google, their support site, or netstat -n command while pcanywhere is activated.
2. Turn on Port Forwarding for that port z for PC x.
3. now, from your work, type in your WAN IP (assianged by ISP) in pcanywhere. you shuold be connected to that PC x