Dmitry,
Inno Setup gets my most enthusiastic endorsement as a product. Its a well crafted piece of software (rock solid) with an extensive amount of features. I particularly enjoy the fact that it stores all setup instructions in a regular text file that you can study, edit by hand, generate via VFP code, or DIFF to compare different versions of a setup script.
Another benefit: Inno Setup executables are extremely small and have no dependencies on other Windows technologies or service packs. This significantly minimizes your distribution and support efforts. (What will you do with all your free time<g>?)
Enjoy!
Malcolm