this car is perfect for the H3

Hello,
Im a newer g35 driver that lives on Oahu.
I love my car but sometimes it is quite frustrating. love the color, the RWD, the power but i dont like the gas mileage oh and my speedometer barely works...
Im interested in modding my car but first have to get it into to better shape.
I changed out my battery recently but didn't reset my driver side window, and now it is sticking. do you think i have to replace my windows motor/regulator or is there a way i can fix this. i tried the hold down for 3 sec trick that didn't work.
Thanks so much