Do you have to be a vet of a war to recieve benefits or just a vet?

It depends, many counties have what is called a "veterans service officer" that could help. I know from personal knowledge that you can contact your local American Legion Post and most have a service officer that can help get you either the help you need or direct you to the proper party for assistance. The party need not be a member of the American Legion Family.

Yes, spouses qualify whether vet is alive or dead providing the vet meets the standard for benefits.
HERE'S A LINK FOR YOU. http://www.vba.va.gov/bln/21/pension/vetpen.htm#7
There are conditions and documentation that is required.
A veteran/spouse cannot receive both Aid and Attendance and Housebound benefits at the same time, but they can receive a pension and ONE of these benefits. The paperwork is extensive and you'll have to provide a lot of documentation. The paperwork info will tell you all documentation that is required. Once submitted the benefits if granted are retroactive to applying because processing can easily take 6 mos. I don't recommend doing it yourself because IF THERE IS AN ERROR in the application, lacking proper documentation or not completely filled out, you have to start all over and it is not considered retroactive anymore since it was wrong. CONTACT your LOCAL V.A they have staff that will help you.
If your Mother gets sick, and your Father qualified for these benefits, she qualifies also if conditions are met.
I hope this helps.