I start Lime Wire 5 up and 5 seconds in to opening it says Windows has found an error and must shut down the program.

What can I do to fix this, is it a bug, java or what?

Well first of all, try uninstalling, deleting the junk files (the files that it leaves behind), and then reinstall, if not then try to update java.
If neither of these suggestions work, do a virus check. Because this happened to me and turned out i had a god old "Trojan" lurking on my hard disk.

thank you, but I have already tried all these, also I have this problem with fire fox every now and then

It might be the Javascript, download the new runtime environment here
Download Java Runtime Environment 1.6.0.12 - FileHippo.com

And if Java's not the problem, see whether the threads below help.
http://www.gnutellaforums.com/genera...ta-32-bit.html

http://www.gnutellaforums.com/genera...k-manager.html

Or use the forum search to look for something like vista crash - there might be more old threads around to help.