I found this lookup for the hijackthis log line:
O21 - SSODL: WPDShServiceObj - {AAA288BA-9A4C-45B0-95D7-94D524869DB5} -
C:\WINDOWS\system32\WPDShServiceObj.dll

http://www.systemlookup.com/O21/236-...ceObj_dll.html

which agrees that this one is "normal".

O21 List
ShellServiceObjectDelayLoad

This entry is classified as legitimate.

It is either part of a legitimate program or the operating system itself.
Removal is not needed.

Item Details
CLSID: {AAA288BA-9A4C-45B0-95D7-94D524869DB5}
Name: WPDShServiceObj
Filename: WPDShServiceObj.dll
Description: Windows Portable Device Shell Service Object