How many incomplete files & how many shared files do you have? LW 5 does not handle too many of either very well.

Alternative would be to download Java 1.6_5 & see if that behaves better. Would need to uninstall 1.6_13 first. I'd also recommend running Crap Cleaner (click on Registry tab) after uninstalling that Java. For the other Java: (JRE 6u5): Archive: Download Java Platform Standard Edition (Java SE) 6u5