You can actually do this just with the Scripts menu by grouping your scripts in folders. I'm guessing you want this drop down to be visible on some layouts and not on others and you thus need a separate drop down listing your scripts.
If you are using filemaker 10, you can set up a script trigger that runs when you exit (drop down list) or modify (pop-up menu) a field.
Make your field a global text field and use Field/Control | Setup... to format it to use a value list that displays your list of script options.
Write a script that checks the contents of the global text field to determine which script should be performed.
Select the appropriate script trigger for your field and set it to perform the above script.
Thanks for the advice. You are correct about wanting specific scripts on specific layouts. This will give me something to play around with for a little while. Still pretty new to the whole filemaker thing. I will give it a shot and see if I can get it to do what I want. Thanks again for the advice and I will let you know if I can get it to work.