Download these tools and install them:-
CCleaner
AdAware
SpyBot SnD
CWShredder
About:Buster
Boot in SAFE mode and run these tools:-
CCleaner --> Click "Options" button and here go to "Settings" tab and uncheck the option "Only delete files in Windows Temp folder older than 48 hours". Click OK to exit from the Options. Finally click "Run Cleaner".
AdAware --> Click "Scan Now" button in the left pane and select the radio button "Perform full system scan" and click "Start".
SpyBot SnD --> Go to "Mode" menu and click "Advanced". Then "Settings" tab in the left pane, and click "File Sets" and here select the file set named "Usage Tracking" and "Tracks.uti". Then click "SpyBot S&D" button in the left pane and click "Check For Problems".
CWShredder --> Run CWShredder and click "Fix".
About:Buster --> Run About
:Buster and click "Start" and then click OK, and then it asks whether it should shutdown Explorer.exe while scanning, click "Yes" for it. After scanning once, it scans for second time. After the scan save the log file and post it.
Reboot to Normal mode. Scan using HijackThis and post the HijackThis log.