Have things just stopped working since you upgraded to Pro? Make sure that your XP firewall's off & then configure PC-Cillin to allow LW.
PortForward.com - Free Help Setting up Your Router or Firewall

Next, delete LW's preferences folder when LW's properly closed. See point 3 here & also point 2 if you've used older versions of LW in the past (there could be a folder in either location).
Fixes for LimeWire
This will kill all of your settings within options, you'll have to go back through afterwards & reset things. If you're not sure of your settings, go through LW's tools > options & write them all down, so that you can reset things later.

Try port forwarding for your router, the instructions are here.
Port Forwarding for the Dell TrueMobile 2300
Don't forget to set up a static IP address first, you'll also need to follow the MAC Address link in those instructions.
LW's listening port, port in the 'manual port forward' box & port forwarded within the router all have to be the same number.

Did you update your Java version when you upgraded to Pro? If you did & haven't been able to connect since installing 1.6.0_01, try using this older Java (some people have had probs with 1.6.0_01 & some can use it just fine). Use the JRE offline installer & remove your current Java version before you install this one.
Archive: Download Java 2 Platform Standard Edition (J2SE) 5.0 Update 11