Having done this a few times already, I thought of documenting this.

As soon as I get a Windows based PC, I usually install the following:

- Openoffice (alternative to MS Office)

- Filezilla (FTP client to transfer files to my websites)

- Mozilla Firefox (free and powerful browser)

- Yahoo messenger (chat software)

- Pidgin (Can do yahoo, google and other chats with this)

- Skype (Voip)

- Gizmo Project(alternative to skype)

- Cdrtfe for windows (lightweight cd writing solution)

- Izarc (alternative to Winzip)

- Context Editor (very good editor for PHP, HTML and in general)

- Revo Uninstaller (Powerful uninstaller)

Most of the above are free and open source. Also, these are proven popular packages.