Not quite sure why Vinod_r2 referred to Java runtime as one really must have it installed or many, if not most, web pages will fail to display correctly, not to mention various interfaces not function at all.
If you have it it will show listed in Control Panel/Add or Remove Programs (Programs/Uninstall a Program in Vista) as Java(TM)......etc.
If shown, uninstall it and download/install the latest here:
http://java.com/en/download/index.jspRegarding the latest version of SiteAdvisor. Mine is 26.6 6261 in Firefox and 2.6.0.6253 in Internet Explorer 7 but I have Siteadvisor Plus, so that may be different I really don't know.
If you uninstalled and reinstalled it then you would have the latest version available for you I guess.