Mughlai food can be cooked hot and spicy. It can also be cooked, not exactly bland, but certainly not hot, more piquant.
It will take time to get used to Indian food, how to order it, how to eat it. Andhra food, for instance, is the really hot and spicy Indian cuisine, one that other Indians fear, and it is best to avoid it until it has been learnt and understood through the tasting of components of Andhra food that happen to be shared with other styles. Bengali food is not hot, unless it is a bad cook, but is rich in oil and spices, not easy to digest in large quantities. Gujarati food will probably suit a beginner the best. Or even Rajasthani, if you get your hands on it.
Also, best to go for a set-course meal; personally, I find eating more than two or three dishes plain gluttony, but in a large group, especially with mixed vegetarians and non-vegetarians, more dishes are obviously necessary.
What is hot and spicy, anyway? Andhra is, for sure; so is Karaikudi. What else? Can someone comment?