A couple of days ago, before I upgraded to the new version, limewire will start loading; once it gets to the part where it says its loading old downloads, the bar goes across 2 or 3 times then limewire freezes. I deleted all incomplete downloads. Didn't help. Upgraded, didn't help. Deleted and reinstalled, didn't help. I've run all kinds of spyware and adaware programs. Normally if something is going on with limewire running those programs or tuneup utilities will fix it. Not this time. I'm not understanding why it keeps freezing once it gets to that point. Does anybody have any ideas? It has worked fine up until yesterday. As far as I know nothing has been done to the computer. If anybody has any idea what I can do, please let me know.

I have windows Vista.

Try updating your Java: Java SE Downloads
Download the JRE offline installer & remove any other Java versions via Add/Remove Programs (in Vista I think it's Start > Control Panel > Programs > Programs & Features) before installing this one.

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 change 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.
Vista users: LimeWire Pref Folder in Vista

If that doesn't help, right click on the LW icon > properties > compatibility. Try running in compatibility mode for XP.

If nothing there helps, try reinstalling LW. See LOTR's tips here: http://www.gnutellaforums.com/320995-post377.html