Wondering how to update Java

Hello, I wonder if someone might advise me on this issue. I have been unable to update Windows XP for some time now and it occurs to me that having had a recent bout with the byte-verify Trojan, and having deleted the infected files, that perhaps I can't update Windows because my Java is messed up. I had replaced Microsoft Java with Sun Java some time back because someone said it was more secure, but I really don't remember what I did to get it, and that was before the infection by the Trojan. Microsoft doesn't seem to want you to use any browser except their own when you visit their website- do they also insist upon their own Java? Anyway, I hear that their latest version of Java is more secure now and I'd just as soon switch back to their product if it would help me get my updates. Would someone please tell me how I can get the latest Microsoft Java and how to install it, or give me any other suggestions that seem pertinent?
Thanks a bunch,
Manticmeister

 

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