Installing SMF is not difficult. SMF is designed so you will have as few problems as possible. Check this document for information on how to install SMF. You will need a host with PHP and MySQL before you begin.
Upgrading SMF to the latest release is quite simple. If you are upgrading from a stable release you can likely do it straight from the package manager! If you are upgrading from one beta release it is as simple as uploading the needed files over the current ones. Stay up-to-date, and you should have no need to worry.
Converting to SMF is rather simple! There are many converters available to convert other forum softwares to SMF. The Converters were designed to have as few potential problems as possible. If something goes wrong during the conversion your current forum will remain untouched.
SMF is designed with the typical member in mind. View these documents to find out all the ins and outs of SMF from the point of view of a forum member.
SMF allows complete control over moderating your forum. View these documents for information on how to moderate your forum, advice on when it is a good time to do so and how you can communicate your forum policy.