I had an HSA with a previous job but I no longer work there and am no longer contributing to it. I still have the account and there is still money in it. My wife recently got a new job as well and has been told that if her spouse has an HSA then she is not eligible for one. So... since I still have the account, is it considered an "active HSA" that would make my wife inneligible? Again, I haven't contributed to it nor has any employer for over six months.
Your spouse is eligible for an HSA even if you have one as long as she is covered by a qualified high-deductible plan. In the case that you both had HSAs you would be limited in how much you contribute each year, but both can have accounts.
In 2015, you could each contribute $3350 to your separate HSA plans. If you have a combined plan, and even if you switched mid year, you could contribute $6650 during that year total to the two HSAs. That can be divided any way you want as long as the total does not exceed that maximum for the year. You can contribute an extra $1000 if you are over 55 years old.
(I should probably also mention that you can still make contributions for the 2015 year until April 15, 2016, because it's relevant to most who would read this. Also you can only contribute a percentage of that limit matching the percentage of months that you are covered, but if you are covered for the last month of the year, you can contribute the full amount as long as you are covered for the ENTIRE following year.)