What can I use to clean grease/dust from hood of exhaust fan over stov

Vinegar is my go to. Cuts the grease easily.

Vinegar works well to remove grease, as does window cleaner. If you want a 'green' cleaner, there are a few more options here.

http://www.apartmenttherapy.com/how-to-green-clean-grease-from-138621

HTH

Vinegar to cut the grease; baking soda or cheap toothpaste as a scrubber if you have baked on gunk.

I use CLR Kitchen and Bath spray. Goes on foamy, leave it sit for 5 minutes, wipe off with damp cloth.

BarKeepers

If you aren't "feeling green", the easiest way is a grease cutting cleanser - even the "Awesome" brand at a dollar tree will work with just a wipe.

That spot sure can accumulate the grease can't it....I use Mr. Clean erasers...they work like a charm!!