My experience as a 47 year-old who was mostly a snowboarder for 15+ years before starting skiing again 6 years ago (and now skiing 90% and boarding 10%).
First of all, take a few lessons. Its not just skis that have changed, but also technique. Plus you're a blue run guy, yours probably needs work anyway. Newer skis are easier on your body and much more forgiving. But if you ski them like an old ski, you won't get the benefits. You may find that you can ski well on skis that are shorter than what you remember. Some of my skis are shorter than what I had when I was 16.
Don't get the standard rental skis. If you're any good at all, you'll appreciate the upgrade to a "demo" ski.