The following programs are all Open Source and Free Software applications for Windows.

Firefox Web Browser
Only the best web browser..

OpenOffice
MS Office compatible office suite

Gaim
AIM, ICQ, MSN, Jabber client

7-Zip
Winzip replacement

Gimp
Photo/Image editing software

For Web Development with WAMP ( Windows Apache MySQL PHP )
Apache Web Server
PHP
MySQL - also get the mysql control utilities

DB Designer 4


My Favorite - DB Designer 4. Use this to model relational databases, and export mysql code or connect directly to mysql.