I would like to recommend you this: »www.iobit.com/malware-fighter.html when you install I think it ask you do you want some 3rd party "Ask" banner thing. Just uncheck that. Remember to update it. and then do a full scan.
As for the rest, it sounds like some sort of shell corruption. Maybe a visit to the Microsoft forum and pointing to this topic - someone may know specific points that need to be unregistered and re-registered or something of that nature to allow it to work with the direct link libraries correctly.
Edit: Something alone this:
Note: XP method, not Win 7 as your's seems. It is an example to help you understand the direction to look at. Some even suggest just swapping themes back and forth will reset the shell for themes. Also switching from classic / optimal / windows options for the user theme may work.
But as you mention malware - I'd ask for a check for your O/S version to obtain the correct paths to review.
It wouldn't hurt to check permissions due to the infection.
Introduction Windows stores the location of per-user special folders under the following registry key:
HKEY_CURRENT_USER \ Software \ Microsoft \ Windows \ CurrentVersion \ Explorer \ User Shell Folders
When you redirect special folders using Tweak UI or by moving the folder to another location, the User Shell Folder registry path is modified accordingly. To reset the User Shell Folders values to defaults, use the information in this article.
Resetting the special folder paths to defaults [Use the Fix-It Tool] Microsoft has a Fix-It solution that fixes most of the shell folder paths (both per-user and per-machine shell folders) automatically. You can download the fix from KB886549 (Thanks to MVP Robear Dyer for the URL.)
If you opt to reset the shell folder paths manually using the Registry Editor, read further.
Added: Some might even suggest creating a new user and deleting the old one, both to define user permissions correctly and also added security involved in changing users due to userland malware functions. -- The only thing necessary for the triumph of evil is for good men to do nothing - Edmund Burke
Just make sure you back up all the data....and if you have an email client you remember to save the .pst file or whatever data file the client uses - I know I've got all chuffed over cleaning and forgot something in the backup before deleting a user and/or profile.