Should I ignore my fractured tooth?

Went to the dentist tonight for a cleaning and she
discovered a fractured molor. It has a large amalgam
filling (of course!) and she recommended removal of
the filling and then a crown. Here are my concerns:

* Safe removal of the mercury. When I questioned her
about her procedure, she uses water and high pressure
vacuum. Doesn't use a dam or alternative air source.

* Are crowns good ideas?

* BIG QUESTION: Can I just ignore this tooth? Not
do anything. Or have the tooth pulled?