I had to double check the date on this thread.

By using
msconfig to reduce unnecessary processes loading at startup.
Have a look in the startup tab and there will be a a list of processes.
There may be things like:-
messenger - msgnr.exe
quicktime - qttask.exe
Do a Google search on the process name to learn what it is and whether it really needs to load at boot time. If it is an anti-virus program then it probably does need to be left alone but many of the other items probably do not need to be there.
Also have a look using Task Manager at the processes that are currently running. Ignore the Windows processes as they must run otherwise Windows will become unstable. These are processes that have the names:-
SYSTEM
LOCAL SERVICE
NETWORK SERVICE
in the User column.
Do a Google search on the non-Windows processes and see what they do and whether they need to be running.