The new task manager is very useful (for beginners too) to check what do you have in the startup and what slows down your boot time.
In the task manager, in the Startup tab you can add some columns like
status,
startup impact,
startup type (so you can check where the program is started),
disk impact, ect...
To do this right-click a column label and choose the columns you want.
In this way you can check how the startup programs impact your system during the startup and then disable the useless ones.