New installation painfully slow - how to investigate?

[joe]

The new Mandriva 2006 install I just finished is painfully slow in some 
applications, particularly Firefox, Konqueror, and Kmail ... much slower 
than my old Mandrake 8.1 system.  I have 512 Meg of Ram and 1 Gig of swap 
and nothing else running while I do these operations one at a time.  What 
would be the recommended procedure to try to investigate and remedy this 
problem?