Using QB desktop, how do I print general journal entries for a specific range of transaction numbers (i.e., the last 100 entries without regard to their effective date)?

"the last 100 entries without regard to their effective date"

The date you put on the JE is its "date", if that is what you are calling "effective" date.

But, you entered them on a specific Date, such as Today, so you can run a report on "Last Entered/Modified".

For example, if you know the "last 100" were entered from August, forward, then run Reports menu > Accountant > Journal report. Filter on Transaction Type = Journal and filter on "Entered/Modified" set the date range as 8/1/2016 to Today.