I have a webpart that works off of a list but what I\'m trying to do create a dropdown that contains a list of sharepoint lists so that when the user edits the page and selects
What you are looking for is called a Toolpart. Take a look at this example for a tutorial on how to create one.
Overall, your general steps will be:
Microsoft.SharePoint.WebPartPages.ToolPartCreateChildControls, write the code to iterate over the lists in your SPWeb, and add those to a DropDownListGetToolParts and add your custom ToolPart so that it shows up in the right hand side