If your wife's benefits (based on her own working record) is $1,350
and YOUR benefits $2,938
both are determined at FRA, then your wife will receive HER benefits first $1,350 plus additional spousal benefits
$2,938 / 2 - $1,350 = $119.
her total benefits woudl be $1469
If she starts benefits NOW at age 62 (before FRA) her benefits wil be permanently reduced - she will get 75% of the monthly benefit because she will be getting benefits for an additional 48 months - and her benefits would be $1102.
There is no "best way" - she will either start benefits now but will have less OR start later and will have higher benefits.
By starting benefits earlier - she will receive additional $1102 * 48 = ~$53k.
If she elect to delay benefits - she will catch up only in 144 months - or 12 years at age 78. So if she will live longer - she may expect to benefit from that delay assuming there will not be any changes in social security laws.