You need to modify the install project. It can be found under the vb directories.
If you have installed vb on the c drive under program files, then the path to look into is:
c:\program files\vb98\wizards\package and deployment wizard\setup1\setup1.vbp
I suggest you make a copy of the project files before you start modifing them.
Once you open that project, you can add and remove any code that you want, so you could form a eula or disclaimer form to pop up and if someone clicks no, they don't agree, then you could terminate the application.
I hope this helps you,
Chi Happens