Thanks again to all who replied.  I have switch type B with plastic frogs, I didn't realize replacing my old track would get so entailed.  My son is moving up from the wooden/metal/plastic Thomas the Tank Engines to his own HO set this Christmas, so I wanted to updated my set to be compatible.  I intend to pick up a controller tomorrow.  Again, thank you all for your time and patience with this old novice.

The tracks have three green wires attached to them, so would the controller you linked worked for me.  Thank you for your reply, this is the first time I have ever posted anywhere, and when I tried to navigate the phone numbers at Bachmann (I'm old fashioned, I like to speak to humans), I wasn't quick enough, so I got hung up on by the automated system, on several occasions, till I gave up.  Thank you again.

I bought a Bachmann First train track pack to replace my old Tyco tracks (My 45 year old engines run great still).  My questions are:  If I get a new transformer , will my engines run on this track, or do I now need to get new engines?  And what transformer do I get to run the trains and switches in this track pack?