Windows 7: Explorer gradually slows down

Am using RTM 7600 version on my EeePC 1005HA, and have been happily using it for my everyday needs. Recently though, browsing files and folders on Explorer has went from mildly noticeably slow to annoyingly long at 5-15 seconds of loading time. I've tried using Process Monitor and Process Explorer and managed to narrow it down to SHLWAPI.dll. What's weird about this is I have Firefox, and browsing the internet is as smooth as can be, but when it comes to browsing my files, it becomes excruciatingly slow.

I've tried numerous solutions I've googled like turning off indexed search, turned off UserAssist logging, turned off a few Shell stuff in ShellExView, and none of them improved performance. If I don't fix it I'll be forced to reformat my HD, but my fear is that I'll be doomed to keep doing reboots everytime, so I want to know what's up.


BTW, when System is idle, around 90% is allocated to System Idle Process while 10% is for Process Explorer. When I try to open a folder, explorer.exe takes all of the CPU usage for around 10 seconds before going back down to System Idle Process.



Any help, or ideas on how to find out what's wrong, would be greatly appreciated Thanks!

EDIT:
BTW, I have Kaspersky 6.0, Photoshop CS4, Microsoft Office 2007, WinRAR among the programs I have installed. Though recently I haven't used them except for Kaspersky, I haven't tried uninstalling any of my programs since Process Explorer always says that it's explorer.exe who hogging the CPU.