Instead of searching for the keys in your emails, manuals and recipes you could use another approach. License Crawler is a sweet little application that scans the Windows Registry for Windows product keys and other serial numbers and licenses.

The License Crawler can discover application product keys and other serial numbers or licenses very quickly and supports all versions of Windows operating system from Windows 95 to Windows Vista.

It is a portable application that can be run from any location and would be a perfect fit for an USB stick. Asking clients to find serial and license keys is often very frustrating. Instead, tech support can simply run License Crawler without having to interact with the client at all.

Wubi is Simple
No need to burn a CD. Just run the installer, enter a password for the new account, and click "Install", go grab a coffee, and when you are back, Ubuntu will be ready for you.

Wubi is Safe
You keep Windows as it is, Wubi only adds an extra option to boot into Ubuntu. Wubi does not require you to modify the partitions of your PC, or to use a different bootloader, and does not install special drivers. It works just like any other application. Wubi is spyware and malware free, and being open source, anyone can verify that.

Wubi is Discrete
Wubi keeps most of the files in one folder, and if you do not like it, you can simply uninstall it as any other application.

Wubi is Free
Wubi and Ubuntu cost absolutely nothing (free as in beer), but yet provide a state of the art, fully functional, operating system that does not require any activation and does not impose any restriction on its use (free as in freedom).