You've got
Microsoft Office Home And Student 2007 installed, so there's no need to have
Microsoft Office PowerPoint Viewer 2003. You can uninstall it.
You must've installed
Windows Live Mail and
Windows Meeting Space and all the other Windows Live-related crap when you installed
Windows Live Messenger. If you don't need it or use it, uninstall it.
If you have any HP devices, don't uninstall any of the HP-related entries.
QuickTime is one of those programs, like
Adobe Flash Player and
Sun Java Runtime Envirornment, that you want to keep installed because those 3 programs allow you to view all the multimedia content in websites. If you're using an outdated version, you can download version 7.64.17.73 from
here. It'll overwrite and replace the old version, so there's no need to uninstall it first.
Everything else in your list can be uninstalled if you don't use it or know what it is.
Take your time to get this done. When you're finished, restart your computer, run a HijackThis scan, then post that new log here.
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