No 2. Cincopa

This elegant plugin allows you to add rich photos, videos and music galleries to you blog with ease. It features some 44 skins to choose from, automatic uploading and hosting, support for iPhone, iPad, Blackberry etc and full screen feature among numerous others.

Go here to download.

No 1. NextGEN Gallery

This is a fully integrated Image Gallery plugin for WordPress. It comes with a slideshow option. It can handle multiple galleries apart from many other features like watermark, templates, JavaScript effects and upload tab integration.

Go here to download.