Which one is better in getting a mortgage? High income or good credit score?

The answer is: both. You need good credit to qualify for a mortgage but you also need to be able to make enough money to be able to afford the new house. So the question you need to ask is: How long will it take to fix my credit?

Also depends on the type of financing you are looking for. FHA you need a 640. Conventional you need a 620 but 10-20% down, versus 3.5% on FHA.