Every time I install windows on my computer I notice it's booting up and starting up really fast, might be done in less than a minute actually.
Later, about a month or 2 (Or sometimes less) you have to notice the startup time is really increasing. When I was younger I used to reformat my hard-disk and re-install Windows. See, I was a geek with a lot of time in hand. Until recently I found and started using a software called Soluto.
Unlike many software that claim to speed up your boot time by deleting un-needed registry keys or deleting temporary and useless files. Soluto identifies your software and tracks the ones that run during windows boot and startup and calculates the time each process needs to finish it's startup.
After it processes your software for the first time (after the first boot) using their 'PC Genome' database. They identify which processes shouldn't be in the boot, and the ones that you might not need during windows startup, and the last type... stuff you should keep in the boot.
What you do after that is your own choice. Just open the Soluto window:-
Click on the "Chop Boot" button, or just point to it. They have some really nice animations. And you'll get a window that looks like:-
You can see the 3 groups of software (another one will pop out later) and in my case the green group (The ones you really won't be missing) is all removed.
And by removed you don't have to uninstall, Soluto gives you the option to either 'pause' a process (meaning it won't run in windows boot) or you can 'delay' a process (meaning it'll run a minute or two after the boot is done).
Soluto is smart and has a great database so it'll tell you many things you might want to know about a process before you make your decision. It'll also tell you exactly how many seconds it's taking this process to startup.
The only thing I hate about Soluto is having to uninstall (and loose my settings) and resintall on every update they have. Which kinda sucks.
They have many other features that either don't work or not that useful (Like choosing extensions to disable to speedup your browser startup, or Crash handling that is not working so far).
But if you want my opinion, you really should have this thing installed on your computer.