Windows 7: Does Windows Defrag defrag system files?

Hi all. Stupid question here...

A friend of mine was speaking highly about this PerfectDisk prog because "it defrags system files." I was kind of surprised because I thought (assumed) that the defrag utility built into Windows 7 already defragged system files. Is this not true?

I do not see an option to force system file defragmentation; maybe that's why I assumed it was already taken care of.

Thank you.

Here is the answer for XP. It is basically the same defrag for Windows 7 with some small changes.
Defragment Your System Files (Pagefile and Registry) in Windows XP - How-To Geek

Microsoft made most of the system files moveable starting with Vista. So yes, the built in defrag can move all the others can. Defragging the page files requires one to do it before Windows boots.

You have 2 options for the funtion you are looking for in PD.

1) Check the Boot Time Box, and reboot.

2) Right Click the Drive you wish to Defragment system Files on, and youll get a menu.

As mentioned, most system files it can Defragment without rebooting. But the PF will need a reboot.

As far as Im aware, Win7s does the system Files only.

Okay, thank you guys. Didn't know about the page files; sounds like the defrag utility is effective enough, though.