It would help to know what advice you've tried

Have you made sure that the XP firewall's allowing LW?

Have you tried changing Java versions? 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

The Acer info that you gave sounds like the model of your laptop. Your modem/router will plug into your computer, or if you connect wirelessly it might be plugged into another computer. Look at all the devices that let you connect to the internet.

Have you tried deleting 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.

Have you tried changing ports? In LW tools > options > advanced > firewall config. Change LW's listening port to 64049 (or something in the range of 49152 - 65535) > Apply > ok.
Looks like something's blocking LW's default port...maybe your ISP? I can't get to Telkom's terms & conditions page to check whether they've got any info about p2p use.