Recently when i was using my Arduino i accidentally plugged 9 volts into my Arduino and it broke ir receiver i had some wires to my Arduino and after that i got a new Ir receiver and when i plugged the normal thing from my computer the Arduino popped. Now i think i broke the electricity regulator?
If you have put 9V on the 5V pin or one of the IO pins, throw it away. It might now be the regulator, but there might have been a reason why the regulator popped, e.g. the 328P or the USB-to-TTL chip are actually broken. So putting a new regulator in is not going to help as it might pop again.