I usually have a self made .reg file for these sort of things, so I can reset th titlebars if they get branded by an isp or company.
Outlook and IE titlebars are usually changed by ISP setup files, so its a common problem and therefore there's plenty of different resources on the net (usually ISP's who don't want 1000's of e-mails asking how to remove their banding) that will explain how to remove the "branding".
As for regedit, as a general rule pop it open, then hit CTRL+F and do a search for the application name that you are having a problem with.