overdrive off on 1995 Ford Explorer

my truck is flashing overdrive off, thats a problem? i thought i should just push the button to turn it on. do i need to fix it or can i just ignore it?
Also, my truck just started leaking power steering fluid could this just be the lines or does the whole pump need replacing?

Asked by for the 1995 Ford Explorer
i had this same problem on my 95 explorer had to have tranny rebuilt $1800.00