After installation and re-boot, I start up either KDE or Gnome and, after
a few minutes, some sort of background activity is going on. Basically,
something (and I don't know what) is scanning my drives in the background -
and at some cost to performance. This is a bog standard installation of
7.0, with no changes made by myself.
This sounds like locate rebuilding the locate database, which it does every
night or nowdays if the machine has been off at some point after reboot. If you
dont use locate you could do
rpm --erase slocate
to remove the package
Hope thats a useful answer.