What I would suggest you do is this:

First of all, look over your planes very carefully and make sure everything is solidly connected - hinges, servo linkages, and so on. Next, check out your radio system to make sure you have something that you can use, meaning if 72 MHz, that you have the approved level of radio transmitter. You may consider moving up to 2.4 GHz. When and if you do, make sure your servos are compatible with your radio system. Some older servos are not.

For radio systems, I favor both Spektrum and Airtronics. But, that is a personal choice. All major radio systems are really fantastic. If you do upgrade your radio system, the majority of folks here usually suggest/recommend that you get the most bang for your bucks.. get enough channels and capabilities to take you well into the hobby. You don't want to have to upgrade in two years from now (for instance) to get more channels when you could do that now. Make sure you replace your batteries.

Once done, go to your favorite flying field and hook up with an instructor and have him/her look the plane over very well. Then have him/her fly the plane for you to make sure all is well.

I would then work with the instructor for a few flights with a buddy box so that you get caught up with your orientation, right / left turns and so on, then get in a good number of approaches, landings, and emergency (dead stick and so on) procedures. Once done, you can probably solo pretty quickly and then pick up where you left off.

Best of luck and welcome back!!

CGr.