RMD age for your husband is 73, not 72. For you it will be age 75.
There is no 5-year conversion rule for those over age 59½. The 5-year period for conversions only has to do with early-distribution penalties and those over age 59½ have no early-distribution penalties. (The 5-year clock for distributions of earnings accrued in the Roth IRA to be tax free is a separate clock.)
Regarding HSA contributions, there is no requirement that you be under age 65, but those 65 and over have usually signed up for Medicare Part A which would make them ineligible to contribute to an HSA, so most people are ineligible to contribute to an HSA for the month they turn age 65 and the months thereafter.
