One form, read by a person, answered in order. What it is and is not the right place for is set out below.
Most messages are about a build that will not install, and most of those are answered already. Check the comments on the title's page and the how to download page first, particularly the section about scanner warnings, which is by a wide margin the most common thing people write in about.
If you want a program added to the library, that goes on the requests page rather than here, so other people can add their voice to it.
Takedown notices are handled through this form with the subject set accordingly. The DMCA page lists exactly what a notice has to contain for us to act on it. A notice missing one of those elements gets a reply asking for it rather than being processed, so it is faster to include everything the first time.