I am post instrumented ACDF C5-6 done in late 2009 for disc disease with posterior osteophyte.
The abbreviated version of my experience.. My surgery went fantastic so much so that within about a week, I did a lovely 3 mile hike (neck brace and all). I was back to work within 3 weeks and back to full activities within 2 to 3 months. It was uncomfortable at first, but I sought pain management through acupuncture throughout the first two weeks. The hospital stay was quick - overnight, and I was walking within a few hours of waking up.
It was interesting that within a few hours of the surgery, I immediately felt relief.
Since then, I have had minor complications. For the first 3 or 4 months, I had issues with sensation on my right side. I couldn't differentiate hot from cold. I had an EMG (which felt like I was wearing a shock collar), which indicated nerve damage most likely caused by the compression. It's taken almost the full two years for most feeling to return and I'd say I'm about 90 to 95% - which I can happily live with. I also found out that neck injury was masking a compressed disk in my lower back. Didn't feel it until after the surgery and now, they want to fix it (no).
I think that my turnaround time - when I started to feel "really" normal again (less the numbness), was about 5 or 6 months. I was pretty freaked out about whiplash or flipping my neck around too quickly. The only activity I probably wouldn't do at this point is ride a roller coaster. Today, I have a full range of motion and zero limitations.
The only caution I have is to fully research what you're going to do before it's done. Surgery is never easy and everyone's going to have a different experience. I read some real horror stories about the same surgery and then made the mistake of watching the surgery on youtube. Kind of freaked me out. But I also think pre-surgery conditioning has a lot to do with my success. I did my best to make sure I was in good physical shape before I was cut open and prepped myself physically for what I knew I'd go through.
Good luck with whatever you decide. I really do feel your pain.