Vista - Vista work something after start up!!!

Please understand that I'm only beginner user especially for Windows Vista.
But one thing that I notice after complete start up is my hard disk work something for a long time[approx. 1 to 1.5 minutes],but i can do my work without any problem.
Can someone explain this issue to me?
Thanks in advance for every reply.
Sorry for my english writing.

ok
there have been a lot of changes in vista since XP.
i can not list them all however i can give you several examples of why this is happening

1. Disc defrag, this is permanently running from the moment you turn on you p.c
2. System restore/shadow copy, this is constantly checking your system for new software...ect and making backups of you system
3. Windows defender, this is constantly interrogating you system for any unwanted nasties and unauthorised start-up programs
4. Windows update, this checks you system to make sure you have all the latest drivers and software to be sure you system is as up to date as possible
5. Windows side bar, any programs/gadgets you have on your side bar automatically go into you start-up shell thus have priority at first boot

there are also many more reasons as to why but I'd be here all week telling you
check out the they can help you loads in understanding vista and what makes it tick

Hi ripbox
Thank for your kindly explain.

Wouldn't all this hard drive activity shorten it's life?

Actually, in addition to what ripbox listed, Super Fetch is usually a big cause of hard drive activity on boot. Once your computer is booted Super Fetch will start caching data (applications) it thinks you are going use.

Don't worry thats a good thing, you programs will load faster after that.