Looking for a sidebar menu plugin

Hi all,

I might be asking for the world here. I have been looking for something suitable for hours with no luck so I thought I would ask the brains-trust in case someone knows of a plugin that does what I am after.

I have just started a job working for a company that, as a side business, gets websites developed for customers. They outsource the larger jobs but I have been asked to learn how to build the smaller sites.

Their selling point is that they sites come with a CMS that give the client the ability to update their own sites. Which is why i am looking at using WordPress.

I am looking to build a site that has buttons on the left that when the user rolls over them with the mouse, the button changes the image (or color, depending on the site). I have been trying to find a suitable plugin but can’t find one that will suit my needs. Most of the plugins only have the text as clickable. I can probably hack around this, but I am concerned that, if the client adds another button then it won’t work correctly (which underminds the selling point that they will be able to maintain their own site)

What I would love is a plugin that appears in the admin site where they user can select options such as the image that appears in the sidebar and the alt image that appears when the curser is rolled over the menu item. I am looking at user-friendly here as the people who commission us to make their sites usually have very little computer experience.

Does anyone know of a widget that will possibly give me the functionality I am asking for? I am even interested in plugins that I have to pay for, so if anyone knows of any commercial plugins, please reply with those too.

Thanks in advance.

Simon