- Windows essentials 2012 is a set of programs, as told in http://windows.microsoft.com/en-us/windows-live/essentials. If you use them, they might be important for you. If you don't, and don't plan to, they aren't.
- Silverlight is used by some websites to show animations and video's and such. If you visit such a site, it's essential. if you never visit such a site, it's unnecessary.
Anyway, programs that are not run don't influence the performance of your system. A program only does that when it's run. So the secret to a well-performing PC: don't RUN programs you don't need. And the secret to a fast-booting PC: don't START programs you don't need at boot. Only you know what programs that are. Use the startup tab of msconfig (from the run command) to check what starts at boot. For advanced users, it might be useful to look at the services started also.
Kees
how important is windows essentials 2012 ? and Microsoft silverlight? i do not know if they are really important to keep. plus my laptop is starting up slow to what it did when i got it new. i hope i am not a bother. i am using a acer aspire e-15

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