Very good

You're infected with TDSS rootkit, which edited your
atapi.sys file.
That was the main issue.
We still need to run couple more checks to make sure, everything is gone.
Uninstall
Combofix:
Go
Start > Run [Vista users, go Start>"Start search"]
Type in:
Combofix /Uninstall
Note the space between the "Combofix" and the "/Uninstall"
Click OK (Vista users - press Enter).
Restart computer.
=========================================================================
1. Download
Temp File Cleaner (TFC)
Double click on
TFC.exe to run the program.
Click on
Start button to begin cleaning process.
TFC will close all running programs, and it
may ask you to restart computer.
2. Go to
Kaspersky website and perform an online antivirus scan.
1. Disable your active antivirus program.
2. Read through the requirements and privacy statement and click on
Accept button.
3. It will start downloading and installing the scanner and virus definitions. You will be prompted to install an application from Kaspersky. Click
Run.
4. When the downloads have finished, click on
Settings.
5. Make sure these boxes are checked (ticked). If they are not, please tick them and click on the Save button:
- Spyware, Adware, Dialers, and other potentially dangerous programs
[*] Archives
[*] Mail databases
6. Click on
My Computer under
Scan.
7. Once the scan is complete, it will display the results. Click on
View Scan Report.
8. You will see a list of infected items there. Click on
Save Report As....
9. Save this report to a convenient place. Change the
Files of type to
Text file (.txt) before clicking on the
Save button. Then post it here.
Post fresh HijackThis log as well.