Does having certification in project management gives one better edge in securing executive positions than with sales/marketing/finance background?

Obviously having some project management certification gives an edge.

PMP and Prince2 are very hot project management certification these days.

Very good question.
It depends on the company doing the hiring.
In some cases employers will overlook the certification if your experience and track record fits the job profile, however it will be expected for you to get the required certification to keep in line with company skills requirements.
Some require PM certification along with a formal degree/diploma or certificate.
It also varies from country to country.