Windows Open source softwares

1) VLC
VLC is one of the most flexible multimedia players available. It supports a vast number of audio and video formats, including H.264, Ogg, DivX, MKV, TS, MPEG-2, mp3, MPEG-4, and aac, and it supports streaming and TV capture cards. VLC isn't limited to viewing multimedia files, either. It can convert and transcode formats, too.

2) Gnumeric
Gnumeric is the spreadsheet portion of the GNOME Office suite (as well as a stand-alone tool). It has been around for quite some time and is an outstanding entry in the spreadsheet world. Gnumeric currently has 520 spreadsheet functions (154 of which are unique) and is faster than any spreadsheet application you have ever tried. Gnumeric can read many spreadsheet formats, but if you're looking for a clone of Excel, look elsewhere.

3) Abiword
Abiword is also a part of the GNOME office suite (as well as a stand-alone tool), and it can serve all your word processing needs. With Abiword, you can create and collaborate. It's lightweight, fast, reliable, and (like all tools on this list) free! Abiword can read and write both Microsoft Office and OpenOffice document formats.

4) Audacity
Audacity is an incredible piece of software for recording and editing sounds. You can use it to record live audio, convert analog recordings to digital, cut/copy/splice, change speed and pitch, and import/export numerous formats. Audacity can also remove noise and add effects. If you're looking for an open source recording studio, don't overlook Audacity.

5) Inkscape
Inkscape is a powerful vector graphics editor similar to Illustrator, Corel Draw, and Xara X. It closely adheres to W3C standard SVG file format, so you can be sure that any SVG file created with (or edited by) Inkscape will work with any other standards-compliant tool. One nice aspect of Inkscape is the availability of numerous tutorials, which you will find on the Inkscape site and on other sites.