Scotch Whisky Tours- seeking recommendations

My wife and I are planning a trip to Scotland and want to tour some distilleries in the different regions (Islay, highlands, Speyside, lowlands, etc).

Have any of you done this and would make a recommendation for the path you chose?

Rent a car?
Hire a tour company?

I know this seems like a travel board question, but I suspect there are scotch drinkers here that can help.

Thanks