what do you mean by tasks? what appears when you log in?
I assumed here you mean the services, like httpd (web server).
There are several methods how you can control which services will be started during boot time, depends on the level of your expertise. There are graphical tools and command line utilities. If you are using redhat distro, theres a services configuration tool, a graphical application. There's also a utility chkconfig for command line.
you may study also about different runlevel.

warren