I can't live without activity, but even a 20min walk leaves a killer headache.
This summer I am going to the beach, so I decided that after 2 years of no activity, I need to do something.
So, for the past 4 months I have been going to the gym 3-5 times a week and just work-out for an hour each time and do very low impact activities. NO Jumping rope !!!
The step machine is great! Lifting light weights are good. I always get a headache within the first five minutes, but I want to look good for the beach, and I need to come back to life. It is good for me.
Now the only way that I am starting to do this is this past summer I had an MRI of my neck and head, as well as an MRA of my head. Both were clear of any problems, so there is nothing life-threateningly wrong with me. Unless you have had this done, make sure you are careful because problems could arise from activity.

Good Luck!