You only need to use the Workbench .adf file when first installing the workbench under UAE. I think WinUAE will be a lot easier for you. I think the installer works well, and I think the documentation is fine (at least I can't remember any major problems). You would need to install and use Workbench if you want to use (Amiga) hard drive installed games. Once everything is installed, it's more convenient than swapping .adf files in the UAE requester.
Here are some links to configured Workbench set-ups with most of the handy utilz etc:
AmigaSYSAmig In A Box (AIAB)ClassicWorkbenchAmiKitCheck out the link to the old website on the AIAB page. I think there is some help on setting up WinUAE there as well.
Of the above, AmiKit is the most recent, and has received good reviews from users here.
Have fun.
edit- Never used Hi-Toro, but it looks similar to the WinUAE interface. I believe WinUAE is still a more developed program though.
HD should be 880K High Density (floppy), and DD should be 1760K Double Density.
To get games running, I suggest you first try just using floppy based games on WinUAE. This should get you started easily enough. Then once you've had some fun, you can take a look at some tutorials for installing Workbench (try the AIAB site). I think there are some others around too. I don't think it should be too tricky. I think you just need to re-familiarize yourself with the old hardware. You can also look around the net for info on the Amiga architecture, which will help you to design your UAE configurations. However, just try to use some pre-made configurations to start with.
edit edit- Sorry, I mixed up the sizes for the HD and DD floppies. They should be the other way around. Also, you probably only need to use the DD option (880K).