I have two forms on a site I'm developing, one form I need to be able to filter by categories and sub-categories, the other I need to filter by keyword, File Type (PDF, EXE) and list them based on their category.
Is Low Search right for this?
Depends on what you're filtering. Low Search will filter channel entries.
Whether you can “list them based on their category” depends on what you mean by that, exactly. If you can generate the output using the native
channel:entries tag, then you can also output it using the Results tag.