Car put into storage now will not select any gears Mazda MX5

when you but it in gear with the engine off is it going in gear?
eg if you try to push the car is the gear engaged

well it would show that the gears are engaging so the gearbox is working.
you could also try jacking it up and turning the wheel to see if the prop is turning

I'm 100% certain that the clutch is not disengaging, rather than the fault being in the 'box.

The MX5 has a hydraulic clutch, so it could be that the seals in the master or slave have failed, resulting in no movement at the clutch when you push the pedal. Quick check if to look at the fluid level - if there's no fluid in the reservoir, then this is likely to be the problem. However, you said that the pedal felt normal, and if the hydraulics had gone they wouldn't.

The other possibility (and the one which I'm 99% sure is the case) is that the clutch friction plate has rusted onto the flywheel - this is more likely the damper the garage is. This results in a normal 'feel', as the likage etc. all works perfectly, but it just doesn't disengage. Worst-case scenario is that you have to drop the gearbox to take the clutch off, but there's a good chance you can shock it free:

-Push/tow the car to a large ard/private drve/etc. Somewhere there's not too much to run into.
-Start and warm through then stop the engine.
-Block the clutch pedal down - you want it trying to desengage, but you want both feet free for the other pedals.
-Put it in 1st gear and start the engine. The car will kangaroo away as it starts, and you'll probably need a bit of throttle to keep it running. This in itself may free the clutch.
-If not, build a little speed so the engine's running around maximum torque speed (5500rpm for the early 1.6), then floor the accelerator with your right foot and immediately stamp as hard as you can on the brakes with your left foot - this will transmit the maximum shock to the clutch, hopefully freeing it from the flywheel.

Do keep your wits about you; driving with no clutch like this is 'interesting' especially if you need to stop in a hurry. If you need to stop you can probably slip the lever into neutral as long as you're not accelerating hard or using lots of engine braking. Worst case, just stall it with the brakes.

Yep, clutch is stuck (and the brakes might be too, so be warned).

Heat soak it and it might come off, as already said. Sometimes starting it with it in gear and with the clutch pedal down can free it, but it's not gentle. The way I do it is to jack the back of the car up and get it secure on axle stands. Start it up in gear and rev the car so the rear wheels spin up. Then with my foot on the clutch I jab the brakes. Always make sure the clutch pedal is down otherwise it can't free off. It's not subtle and many say it's unsafe, not really sure why... But it works every time for me.

I've had this same problem. As said before, foot on clutch, select gear, start engine. Mine came loose after the car leaped forward a meter or so.

Thanks for all of your help.

I started the car up in second, gave it a boot and stamped on the stopper.

Everything went back to normal and the car is outta here.

Thanks for all of your help.

Are you sure you haven't got a slightly weeping hydraulic system with a little air in it?

The long curly metal clutch pipe almost always has some air in it, a real curse word to bleed properly!