what does this mean?
"George is doing a hell of a job during very difficult times, more power to him. Screw all them people who don't like him."
Is it in favor of George or against him?
what does "i'm doing hell" means?
The phrase 'a hell of a' - sometimes even written 'a helluva' - followed by a noun of some sort has meant that the person/thing concerned is outstanding in some way, good or bad. It has been used in this way since the 18th century.
Thus, you might see "He's a hell of a brave guy!" (good) or "This place has a helluva climate!" (bad) or "She's a hell of a fine teacher!" (good).
In the example you give, George - according to the speaker - is doing his job extremely well...that is, the speaker is very much in favour of him.
In the aftermath of the Katrina hurricane, George Bush was seen on television with the head of the emergency service, whose surname was Brown. Bush said "Brownie, you're doing a hell of a job". Brown smiled appreciatively. Then Brown was sacked for alleged incompetence.
The point about the phrase, Weirdo, is that it can be good or bad, as I explained earlier. "You're making a hell of a job of that, mate!" can just as easily mean "You're making a total dog's breakfast of it!" as "You're doing it excellently!"
The reason we can tell, in your example, that the speaker is on George's side is from the other clues provided.