Update your Java & see if that helps. Use the JRE offline installer & remove any old Java versions before installing the new one.
http://java.sun.com/javase/downloads/index.jsp
Go to tools > options > uploads & untick the box to share partially downloaded files > Apply > ok. Now delete the files from your incomplete list & restart LW. If that doesn't work, try deleting the files from your incomplete folder outside of LW. Go to your LW library, click on Incomplete Files & click Explore. Once the folder's open, delete the files from there. Reboot your computer, restart LW & see if they're gone. Are you getting an error message when you try to delete the files?
If these things still won't delete, try one of the tools here. I've used Unlocker & DelinvFile (ask-leo link) & they're both good.
http://www.gnutellaforums.com/showpo...35&postcount=2
Otherwise, I'd suggest scanning your computer for viruses!