Help! Cracked casserole dish....
I agree. Throw it out!!! Or else glue it and use it for display only, if it is that important to you. Never cook in it again; never serve food in it again.
Are you willing to risk the darned thing breaking in your oven and spilling the contents all over the bottom? The resultant smoke and possible fire? Glass in your food and a ruined dinner? Lead seepage? Huh? Is it really worth it?