Hi Molly!
I think you've picked two great times to visit Walt Disney World for your first trip! I love both times that you are considering!
During September, the weather is just starting to cool off and most children have headed back to school resulting in lower crowd levels at the parks. September is usually a good time to get a great deal too. This year Disney is offering its popular
"Free Dining" promotion. This is a popular discount that really helps on the budget! And maybe you can save enough via the promotion to off-set the cost of staying at Port Orleans!
Another great event happening in September is the Mickey's Not So Scary Halloween party. This party is one of my favorites. The parade is absolutely a must-do!
November is another great time to visit as well. Instead of Halloween decorations, you may see Holiday decorations and experience Mickey's Very Merry Christmas Party! Watching the snow on Main St. and Cinderella's Castle draped in lights is an incredible sight!
I personally think the upgrade to either Port Orleans resort is worth every penny! While I love the All Star resorts, our kids really love the pool slides at the moderate and deluxe resorts. Port Orleans also offers a water ferry to Downtown Disney, which is a nice change of pace.
Hope this helps! Have a great time on your 1st Disney Vacation!