Michaelmantis: To respond to your questions:
1). Can "anyone" go up to the observation deck to view the fireworks or do you need a reservation
It is my understanding that they no longer allow non-diners access to the elevator that goes to this floor.
2). Does it make absolutly no sense to eat there once the fireworks are over (I know they have good food but our reason for going there is the great view!)
They have a great atmosphere, terrific food, AND a wonderful view.
3). I'm going with my mom (I'm 24) will we enjoy this place??? We only have one day at the parks (Going to EPCOT) and I thought that going to the Calif Grill would be a good way to have a "Magic Kindgom" expierence without actually being in the park...
You and your mom would ABSOLUTELY enjoy the experience here. The first time I took my DH to WDW was for our 8th anniversary. This is where we dined our first night and we have INCREDIBLE memories of the evening. The fireworks over the castle were just the 'icing' of the night. They were a wonderful touch of pixie dust and I personally feel this to be a MUST DO for the two of you. If you don't want to do dinner, go for an appetizer or dessert. DH and I always share a meal here which is much less expensive and there is plenty of food.
We are taking another couple (he is turning 60 that week) to WDW for their 1st visit, and this is where we will be on our 1st night. Be sure and take a camera - there are sure to be some Kodak Moments for you to save.
Remember, Disney is about an 'experience' and family -- make the memories and treasure them. I lost my mom 8 years ago -- we never did get to go to WDW together -- but she loved looking at our pictures and seeing the videos we took. DH didn't want to 'carry around the camcorder all day' but when we saw the smile on her face he was glad he did! Now he doesn't complain at all, even if our kids/granchildren don't rush over to see our home movies now (boring), one day they will. They will appreciate how precious and enjoyable life can be - and know we never missed an opportunity to STAY YOUNG AT HEART.