Access 1997 or 2003 or 2007?

Been using Access 97 for years.  I use a statistics add-on (Total
Access Statistics) which is kind of expensive and I haven't found
anything to be gained by upgrading. But I'm now told I probably should
because of memory issues with Access 97 which are getting increasingly
fussy.
I'm told that, at best, Access 2007 isn't really very good, that the
better memory management came with 2003.
Any thots? Also, is Vista really that bad?