When the husband dies. And the Widow is 62 years old.
What percentage of the husband's monthly social security check does she
Received. Someone told me it was 75% of his take home amount. She has
Never worked, the husband was 75.

Does anyone know?

The final amount will have to be determined by the Social Security people. They will decide if the widow can receive more benefits on her own work record versus the work record earnings of her husband.

Also, just how old was the husband at the time of his death?

It is 75% of his SS benefits. Whatever he was getting for SS retirement, you as a widow will receive 75% of that. If he has surviving children under 18 they will share his benefits with you. So not 75% of his take home pay but 75% of his SS benefits, whatever that amount was.