Here's my take on your questions :
1. Gum should be ok as long as it's sugar free
2. Pepperonni should be ok too. I love to eat salami, kabana and cheese kransky's !! The only issue with this is that meats preserved with nitrites can cause cancer, so maybe minimise consumption of these.
http://en.wikipedia.org/wiki/Sodium_nitrite
3. Cream cheese is fine and i'm sure sour cream should be ok too, check the label to see how many carbs are in it.
4. Diet sodas - For me, I like to drink Pepsi Max but I do limit it to no more than 2-3 cans a week. I used to be addicted to the stuff - buying it by the carton. Now I drink water with my meals and during the day.
With regards to the whisky, someone at work told me that never mix spirits with diet coke as it forms a nasty compound in your gut and "gives you gut rot". I'm, not sure about this, but I don't like the taste of DC anyway so don't drink it.
I'm pretty sure that with alcohol, it will be used as energy first by your body, so it will stop you from burning your body fat until it's energy value is burned by your body.
However, I think spirits are preferred to wine or beer, as I think those drinks have extra carbs in them.
Don't be too worried about the scales yet. I would focus on your food portions, drinking lots of water and exercising. Your weight will fall, don't worry, and expect a few stalls here and there.