I am trying to make an application as easy to deploy as possible for Windows and I am trying to choose between packaging the application as a .exe or using an installer. I was wondering if anyone had opinions on the relative merits of either way? My preference would be to use a .exe as it would be just click and run for a user.
In general, standalone executables are much easier to work with. They are easy to move, delete, run from a portable drive, etc due to a lack of external dependencies. If your app does not need registry settings or does not require certain libraries or helper utilities to be placed in system folders, then a standalone .exe will fit your problem.
If you do need to modify the registry, install files in different locations, create subfolders, etc, then you will need an installer of some sort. If you provide an installer, make sure you provide an un-installer as well (and make sure that the uninstaller doesn't leave behind orphan registry entries or temporary files).
To solve your problem both ways, you can have a single-file executable that is installed via an installer. That way, you get the benefits of both approaches (not to mention that the installer would be very easy to write in this case). I have also seen some apps that are available for download either as an installer or as a bare executable (let the user choose their preferred delivery option).