Looking of an complete open-source CFD software combination
 

Hello everyone,
I've been searching this forum for several days now, but I did not find what I was looking for.
I'm looking for opensource solution of CFD software (linux/windows) with GUI, but as I figured during searching this forum, there is not simply one software, which can do everything. Or it can but, there is almost always some part "missing" or not as good as in other solutions. So my question is: What is "the best" combination of software for you. I'm looking for the examples and suggestions.