Vista - Vista, temp files and the odd query.

I recently discovered on my ASUS note book, 2.2 Gigs of
"temp" files in the windows\temp folder, they were
mostly date stamped March 2007 which is when I fired it
up for the first time and the OEM Vista Home Premium
went about setting itself up. Yesterday in an admin
account I asked Vista to "clean up" all useless files
and it removed a paltry 2Kb and left the 2.2 Gig
in the temp folder. I ran windows explorer, high-
lighted the files and hit delete and clicked through
the Vista "do you know what you are doing boxes" and
the confirmation box froze, I rebooted and the files
were still there, so I highlighted the temp folder and
hit delete and Vista dumped the folder into the bin as
quick as a flash, I created a new windows\temp folder,
rebooted, emptied the bin and reclaimed 2.2 Gigs of
disk space. I am wondering why I had to clean up my
Windows Vista.? Why do I get the message that "windows
calendar has stopped working" on my standard desk top
but the message does not appear in the admin account
and two other accounts for family members.? Why did my
DVD burner drive vanish from windows explorer while
transferring files to an USB memory stick.?

jess