I would not recommend the use of any drain cleaning chemical.
You may use something like Bio-Clean as a drain maintainer but in your situation it is unlikely that it would give you the instant results you are looking for.
I would recommend using the services of a plumber to snake the line clear then use Bio-Clean to maintain it. I would also look inside the disposer to make sure that the grind chamber is in good condition. This is very important if you have one of the "Lower Grade" disposers like the Insinkerator Badger line installed. These have galv. steel grinding teeth and they do wear badly after a few years. If its one of the older blueish looking ones you don't have to look... It's Toast!