Decrap is a portable tool which can automatically uninstall multiple programs in a single operation. The authors have designed it to "safely remove all of the bloatware that comes pre-installed... on a new Windows PC", but it could save you a great deal of time in cleaning up older PCs, too.
The program is essentially a simple wizard, and after a little preparation it presents you with a list of everything it can remove. This includes third-party tools, desktop files, startup programs, drivers, and what Decrap calls "Windows related software" (mostly Visual C++ redistributables, on our PC at least).
This is quite an extensive list, and initially at least Decrap will select many of these options by default (it'll wipe out all your startup programs, for instance). It's easy to clear them all again - just check and clear the checkbox to the left of the section name - but you do need to be careful that you don't delete anything important. Although Decrap does at least try to help by creating a System Restore Point after you've decided what to clean.
So far this may seem relatively ordinary, but that's because Decrap has saved its most interesting features for the very next screen. Here you can opt to run your chosen uninstallers entirely automatically, and clean the Registry immediately afterwards.
Just to be clear, this doesn't mean run a regular "silent uninstall", which is only supported by a few applications anyway. What Decrap will do is launch all your uninstallers in succession, have them display as usual, and automatically select their buttons and options for you. And so, in theory at least, you could have the program remove hundreds of applications from your PC, all on its own, while you get on with more important things.
It's not quite that simple, of course.
The first issue is the Decrap has to close all non-system processes before it can begin, so you're not able to run any other program as it's working.
And the second is that, in our tests at least, Decrap can't automate all uninstallers. It did well, correctly removing most applications, but in one or two cases it was left hanging, or the uninstall simply didn't work.
Still, if you do need to remove a lot of programs from a PC then there's a good chance Decrap can help, and the program could potentially save you considerable time and hassle. It's certainly worth a try.