Plugins Recommendation.

Plugins are the pieces that make up a server they are what define it here are some of the plugins I recommend on any server.

Essentials: This plugin takes a lot of space but it is quite essential to a server though there are many plugins like this that take less space.
Permissions: If you want specific people to be able to do specific things then permissions is the way to go just make sure you know how to configure it.
Logblock: Logblock is essential for those who have the "do not grief" rule it requires a database but there are replacement plugins like this.
World Edit: Exactly like its title it edits your world and if your staff are making something big then this might help.
World Guard: If you want to protect your world the world guard is the plugin to go.

These plugins are what I think the general list that is needed for a server these are not restrictions just recommendations feel free to mess around with your plugins to create the server your proud of.