Hi Mandy,
I have been lurking on DIS forever and since I love weddings, have spent quite a bit of time perusing the wedding board and seeing everyone's plans and ideas. I have to say there are some lovely wedding being planned on this board!
Ok, now I'm going to say something not so nice, I hope its not too upsetting considering that you don't know me
please take it in the spirit its given in. I actually registered just to post this...
My grandparents both passed away, one when I was 9 the other when I was 12. I was very close to them both. I would have done ANYTHING to have my grandparents there for my wedding, but sadly couldn't.
I know you're frustrated with your inlaws, etc., but please, please take the time to put the dress on, even if you feel silly, to give your fiancee's grandma something to see and be happy about. We will all get old some day. Today you're seeing this through the eyes of an impatient young bride. Imagine being 95 and unable to do the things you long to do, to be with your family at such important events. Imagine how wonderful and special and beloved it would make you feel if your grandson's fiancee spent the extra time and effort to let you know that you are important, that your feelings still matter.
As you said, she's 95. Imagine all the heart ache and sacrifice and love that went into those 95 years. Imagine the heatache of watching your life slowly slip away.
The more you strive to find middle ground and harmony with your inlaws the less tension there will be in your marriage.
Also, since I haven't commented here before, I think your reception location is lovely. I think rather than go so strongly toward an animal theme with the cake,
you might want to consider a "casablana" style. Imagine how lovely, a '40s piano bar, retro stylings, elegant hollywood chic. Its just a suggestion.
Good luck and best wishes to you, and I hope you take this in the spirit it was intended.