What is the best time for stand-up scrum meetings?

Depends on the team. Try different times and evaluate in an agile fashion :-)

Personally I find start of businesses day Monday to be ideal since it provides an ideal time for both “we did this last week” retrospective review and “we will do this stuff this week” forward planning.

When managing software engineers, 2-5pm local time is often a time of high productivity. I try never to book meetings or interrupt them during that time.

One hour before I get to work.