parameter as a drop down list

I am very new to access and would like to have users select report criteria from a drop down list of clients before running the report. The Client names can be lengthy, so asking users to type for parameters will not work. I have built mo开发者_如何学编程st of my function with macros and am intimidated by the code builder. Anyone willing to help a beginner?

The task is:
You have some report that needs to display data filtered by user selected value(s) on the form
The screenshot below (MS Access 2007) shows the basic setup for this scenario:

Please not this simple solution does not require any VBA code.

Below are the key components:

1. Form's drop-down:

   

2. Macro setup:

   

3. Report. Please note the RecordSource is just Clients table (no WHERE clause etc.):