Can I set a password for the users who are going to open the file, and set the rights they will have?
Yes, using version 2.0 Professional you can generate encrypted PDF files or encrypt existing PDF files using 40-Bit encryption. In version 2.1, you can use both 40-Bit encryption and 128-Bit encryption.
You may set both a user and an owner password. The owner will be able to do all operations on the file including changing the password while the user will have access to specific operations that you set.
Please note that 128 bits encrypted PDF files are viewable only in Acrobat Reader 5 and above.