Fun fact: Most "Indian" restaurants in the US and UK are actually run by Bangladeshis.
In any case, I love Indian food, but not the stuff they serve at most of those restaurants. It's always greasy, trashy Punjabi food so it's essentially street food from one region of India (and Pakistan). I love biriyani, but it's not supposed to be so oily and salty. If you eat a curry at one of these places, it's basically just a bowl of oil and salt. Curry is supposed to be vegetables and/or meat cooked in spices, not dumped into a bowl of oil.
Also, I would try non-Punjabi/North Indian food. I went to a South Indian place and had something called Dosa. It was good and the Dhal with it was great:
