Welcome to Healing Well! I found this forum at about the time I was trying to make a decision as to whether or not I should have the surgery. I'm happy to say I had it in February 2009 and have been very happy with the results.
Your surgeon will be the best one to talk to about when and how much you can do in the gym. There are quite a few gym enthusiasts here, and there's actually a weight lifting post-Nissen thread you could check out.
Here's a link to one of those threads:
As far as eating normally, it's a gradual process and there's not a specific time I can tell you. I do remember that we went on vacation after the 4 month mark, and we ate out nightly. I was able to eat anything I wanted, however I had to eat more slowly and chew carefully. I still chew my food thoroughly.
Here is my early recovery journal. It'll give you an idea of what the first few weeks of recovery look like:
Again, glad you've joined us. Good luck with you decision!
Nissen Fundoplication 2/09
"Whatever you fight, you strengthen, and what you resist, persists.”
“Worry pretends to be necessary but serves no useful purpose”
“Accept - then act. Whatever the present moment contains, accept it as if you had chosen it. Always work with it, not against it.”