To optimize the way windows starts we need to see how many services are running and disable one's that are not required a online wizard to do just this is available here.
to remove unnecessary programs from starting up with windows everytime click on start>run>
and in the run dialog type msconfig click on ok.
from the startup tab unckeck all the programs that you don't need.a huge list of programs that startup automatically is available here consult this to decide if you need a program or not.
next we need to remove unnecessary programs that you don't use anymore from start>settings> control panel>add remove programs
we also need to remove temporary files,you can use a tool called disk cleanup available from start>programs>system tools>disk cleanup
the above steps should make your computer run at least 10% faster then before
Will post more tweaks in the coming weeks.