The windows key+R brings up the run dialog. Type gpedit.msc and hit enter. You can customize alot of various windows settings with this, almost all of which come with detailed explanations.
Typing in services.msc will bring up the services dialog which allows you to configure, yup you guessed it, all windows services. There is alot of unnecessary stuff running by default, disabling alot of these will speed up your start time considerably and free up system resouces. There are plenty of sites around that describe these services including which are ok to disable and which aren't.