they go to drysuit heaven...
however, you could use the shell as a practice suit to learn dive suit repair skills, provided you have the time and interest in that. or say you plan to do a cuff seal replacement on a new expensive suit some years from now, then if you still have this one, you could do a practice run on it first with an old seal.
otherwise- if you plan to toss the suit, then remove the valves first, and if they work, keep them for backup/repair parts, or take them apart just to see what's going on inside (in case you need to fix a valve in the future). or say this suit has an adjustable shoulder exhaust valve, and suppose you end up with a suit that has only a small cuff dump, then you could switch to this suit's shoulder valve, or use it for an OPV (if that's a concern).
give the zipper a good cleaning too (wash with toothbrush in warm water, pick off old/excess wax (especially from the end where it tends to accumulate), and burn off frayed threads... if you can get it to work, maybe it's worth keeping as a repair part, either for practice in case you think you might ever do a zipper replacement yourself, or maybe to use for some home project. for example, if you break a wetsuit zipper on an old suit and are consequently about to toss said suit, then you could first try replacing it's zipper with this suit's dry-zip if the size fits... i mean, I wouldn't use it as a replacement part for anything important since you said it's in poor condition, but it could still be of some value in a less important and/or practice project.
If the socks or boots fit, then keep those too in case you end up with another suit with ill fitting socks/boots. And to that end keep the sleeves too - maybe you'll end up with some used suit that's too short in the limbs, but otherwise nice, in which case you might be able to use the legs and arms from this suit to extend the other ones.
The material from the seals could also be used to repair tears/rips in your future drysuit seals, so keep those. or if you can get the seals off cleanly (this is a good chance to practice that by the way), then you could even keep them to use as emergency replacements, or to use them for some home project. For example, you could glue the wrist seals on a pair of cheap smurf gloves to try out how you would like ringless drygloves or similar. or just make a pair of ringless drygloves for a friend to try. Now I don't know whether your drysuit has latex or neoprene seals, but either way, if your next suit has different type seals, and you like them less, then you could try replacing them with the seals on this suit (depending on the condition of these seals - obviously if you need to replace the seals, then you might want to use fresh ones lest all your work be for naught). and look into proper storage; maybe some silicone spray followed by vacuum sealing and storing in a cool, dark place away from ozone. Not sure if the fridge would be good, but I think cooler is usually better... Some (mostly tech) divers carry a replacement wrist seal in a drysuit pocket to use underwater or between dives for emergency field repairs; something to do in conjunction with dry glove rings I think, but I'm not sure about the details right now, I just read about it somewhere.
I am considering cutting it up for patch material or using it for a halloween costume but I dunno...
