Windows 7 Slow Boot (Sometime).

My Windows Boot Really Slow Sometimes. When Windows Boot Logo Appears (Splash Screens) After that Black Screen Appears and My Hard Disk Activity Light Just Stuck , After Sometime (1/2 of Minute Approx) Login Screen Appears and i Login and Then Windows Take Too Much Time To show Desktop properly and Running BackGround Programs..
Now Sometime It Happens that My Windows Boot Really Fast , (Like No Black Screen , Instantly Desktop Appears , Programs Loads) , So i don't Know Why Sometime it Boots Slow And Sometime it Fast .
i also Uninstall the antivirus (SOmetime antivirus Cause Issue) but Still same Slow Boot ..
So Some One Please Help me To resolve This Issue ... :)
My Recent ntbtlog.txt is Attached (i Didn't See any unusual Thing/activity in It)..

Hi FurqanHanif

Welcome to Windows 7 Forums.

Can you tell me what software you use to do disk cleanup and how often you run it?

i Use Ccleaner , and i use it Once a Week ( Sometime Once in Two Weeks) ..

Microsoft Security Essentials , and i Re-install it ..

FurqanHanif said:

i Use Ccleaner , and i use it Once a Week ( Sometime Once in Two Weeks) ..

This seems like your issue.
When running CCleaner you should uncheck the [Old Prefetch Data] option.

Your system is building a list of things you like to do so it can serve them to you just as you request them, or right before. You're cleaning it out each time you use CCleaner.

This will result in inconsistent boot times. I would expect your system to boot slower after you run CCleaner and clean prefetch data.

Uncheck that option whenever you run CCleaner unless you do want to clean the prefetch cache.

Boot times should regularize within a week.

@thrashZone What Do You Mean By That Exactly ???? i installed Software Etc (Vlc , Chrome etc)..
Old Prefecth is Already Deslect , i Never Selected It...

Only Microsoft Security Essentials , No Other Security Tool/Software i Installed Ever..