Essentials for a Wordpress Website

Latest Wordpress Installation

Nextgen Gallery

Image Manager

WP-Lytebox

or

WP Highslide

-

Wordtube
JW Media Player

Angsuman’s Authenticated WordPress Plugin
http://blog.taragana.com/index.php/archive/angsumans-authenticated-wordpress-plugin-password-protection-for-your-wordpress-blog/

Flexipage widget

Google Analitics Plugin.

this one too.

Theme Tester