dds.scr malware prep froze my system

Hi, all. I had posted in security as per below, wherein it was suggested I post in malware section, so I assume I'm now in the correct forum.

Please see this for background:

http://www.techsupportforum.com/foru...re-852730.html

Update:

When I downloaded dds.scr, then clicked it, it caused my system to freeze up, with a teeny [immovable] box superimposed on Desktop stating:
"running in silent mode"

My cursor disappeared, replaced with an hourglass.
Tried CTL-ALT-DEL - but that failed to work.

So I shut off via power button, and now at least able to get back online.
However, a question-mark suddenly appeared at left of SysTray

See attached screenshot

Also:
Even as I'm typing this, I can't type quickly, because there's a pronounced delay between keystrokes, and the letters displaying on-screen.
(They were delayed before, too, but not this much).

Attached Images