Hi Globetrekker,
Looks like the detections are in Windows' temporary locations. I recommend booting into safe mode and running a Disk Cleanup (right-click the C drive, Properties, Disk Cleanup) - that will delete all the files that are in these temporary locations, as well as IE's temporary files, etc. Perform a full system scan in safe mode, too. Hopefully that will do the trick, as in safe mode Windows just loads a bare-bones version of itself, usually without any threats being loaded.
Here's a good article that may help:
What Does "Risk was partially removed" Mean? Generally these results happen when Windows has been "tricked" into protecting a malicious process. A scan in safe mode is usually successful.
You may also wish to set some harmless program, like notepad.exe, to be the default for Windows to use to open .qef and .qsp files. (that's the extension of the Trojan Horse that is being detected.) If the threat does evade Symantec's attempts to stop / delete it, it might then be tricked itself into doing something harmless.
Final piece of advice: the screenshots show that you are using SAV, but what version? Once this threat has been successfully deleted, I strongly encourage you to upgrade to SAV 10.1 MR8 or MR9, if you are running anything less recent.
Let the forum know of your progres, if time allows!
Thanks and best regards,
Mick