Arsenals form is better than forests but that doesn't mean that their form is sound, compared to the previous season I think that they are a little slow now. This game is a tough one and your verdict isn't far from what I had in mind. Nottingham wouldn't want to give up easily so it would be a defensive game on their part which can lead to a draw but the chances of arsenal winning this game is quite high to me
For me at the moment there are only a few opponents who are equal to Arsenal like Liverpool, Chelsea and Manchester City while other teams not so playing against Nottingham is not a problem for Arsenal especially they are playing at home, we also have to remember that Arsenal were previously beaten by Liverpool so they have to win this match to stay on track. What we are looking forward to from Arsenal is the next match against Manchester City on September 21 I hope they don't lose any more points.
I am a fan of Arsenal but I honestly don't trust them to even beat Nottingham forest in their coming game, Arsenal is a club that i believe is very well known to always disappoint themselves and their fans when such is least expected of them..
On the Norm and like you have said, this match is very important for Arsenal to ensure that they win, they can't even afford to end the game in a draw with Nottingham forest because that would also mean that they will have to slide a bit back on the league table..
So, if they really want to keep their current position or even try to enter the first position which is currently occupied by Liverpool, they(Arsenal) must ensure to beat Nottingham forest in their forthcoming game encounter, but I am sensing that this match may likely end up ending in a draw or worst of all, Nottingham forest beating Arsenal.