In teluguites some families practice tradition of remarriages of young
widows. But families which do remarriages to widows aged above 35-40
are very less. Why dont telugu families raise up to the level of
remarriage of aged widows?

There is nothing wrong in doing remarriages to aged widows. Even widows
aged above 50 years can remarry. Life parteners are necessary for women
in old age also.

Yes. Widows should have right to remarry in any age. It is difficult
for widows to live alone in any age.

Doing remarriages to widows is good practice but deciding age limit for
remarriages do not look appreciable. Remarriages of aged widows must be
also encouraged.