I need to grow a beautiful flower for a project I am doing. My limit is about 6 months, and I live in Bahrain, which is EXTREMELY hot/humid weather, especially in the summer which gets to about 40 degrees Farenheit at its hottest. I can grow inside though.. but have any idea on which beautiful flower is the easiest and fastest to grow? I heard a rose can take up to a year

A rose can take up to a year if you start it from seed, but if you take a cutting and give it the proper amount of light and water then it will usually bloom it's first season. There are quite a few roses that handle hot weather quite well. Here is a site that shows you how to propagate a rose cutting.
http://www.scvrs.homestead.com/Cuttings1.html
Here is a list of roses that do well in hot humid climates. Stay away from the hybrid teas though. Hot may be good, but humid is not. They suffer from disease too easily.
http://www.weeksroses.com/RoseClimateHotHumid.php

Oh, by the way, in case you decide that a rose will not work, 6 months is enough time to grow just about anything.

Good luck

weeds and 40 degrees? u mean 140?