Well it depends what you mean by a bad transmission. If one of the gears is broken in the tranny or it won't shift right I highly recommend you don't drive it. Let me put it this way, if you are unsure of it, play it safe and don't drive it. I just replaced my transmission in my Ford ZX2 (I'm 21 and I don't consider myself a gear head), so it isn't impossible to replace yourself. I would recommend you find out what EXACTLY is wrong with it before you drive it or proceed to get someone else, or yourself to fix it. If you want to fix it, it really isn't that difficult, just set aside around 14-18 hours of time (to start with, I know it takes a while), to get your tranny out and fix. Then maybe around 8-10 hours to put it back in. This is with no prior experience and using an online guide to take it out and fix it. Make sure you label everything and keep all the parts and bolts accounted for any labeled and put it with what it belongs with. But to answer your question very blunt no I wouldn't drive a car with a bad tranny, but like I said, what do you mean by "bad transmission"?
bad transmission
It means the transmission is bad.
Parking brake not released, bad torque converter, bad transmission shift solenoid or bad transmission in general, broken shift cable not engaging the transmission.
Yes; it could damage the transmission.
Yes, if it is in good shape and well kept. A car could have a thousand and be in bad shape and not safe to drive.
Safe, yes, smart, no. Damage can occur to the Catalytic Converter.
It is not safe to drive a vehicle with a fuel leak, but if this is the only way to get it to be fixed, be careful that the leak is not that bad if you drive it. A trickle is bad, any more than that and driving it would not be advised.
No fluid bad clutches in the transmission bad or broken linkage no driveline motor not running
vibrations are not bad for a car it vibrates every time you drive, but for safety i really think that with a flat spot on a tire it is not safe to drive on.
no because your car can die or the transmission might slip. you can have a clogged Fuel Injectors , your fuel filter can be dirty and need to be replaced. In so rare cases if your car is jerking to hard it can resulted in a bad transmission.
Depending on how bad the mount is. It may be safe but should be replaced as soon as possible to prevent any damage to the moving parts on the engine.
No but, be sure it has come to a complete stop before you put it in park.