You need not be specific about every little item - most families understand the distribution of personal effects. Real property and expensive items are those usually set out as specific bequests. If dependents are infants or unable to look after themselves, a trust may be set up. The executor may oversee the fund for the education of children, etc. Only the original signed Will has any legal effect.
Photocopies have no power.
Therefore, you should keep your Will in a safe place - a Bank safety deposit box, lawyer's office, etc. If they are not, additional and needless expense may occur at the time of death if the intent is to give the home to the spouse anyway.