You get a missing nail.exe message because there are still references to it in the registry.
Also, desktop.ini is a file that is part of Windows, you see it because you have hidden files/folders turned on. Normally the file is hidden from you, don't worry about it.
Click Start-run and type "regedit" and hit enter.
Once in there, hit F3 and type "nail.exe". Search for and remove references to it.
Also do a search on your hard drive for "Nail.exe" and remove traces there as well. Usually in c:\windows\nail.exe.
Nail.exe, however, is not the PRIMARY bug, it is created by another one, which hopefully you've got removed. So all that's left is to delete the traces to nail.exe in the registry.
Then go into My Computer. Click Tools-folder options, and tell it to hide hidden/system files. Your desktop.ini will go away.
I suggest you run a tool called regsupreme (
http://www.macecraft.com/regsupreme/. Clean whatever it finds. Just do a standard search.
That should do it for those two.
Remove these from your HJT:
F2 - REG:system.ini: Shell=Explorer.exe C:\WINDOWS\Nail.exe
O4 - HKLM\..\Run: [QuickTime Task] "C:\Program Files\QuickTime\qttask.exe" -atboottime
O4 - HKLM\..\Run: [KernelFaultCheck] %systemroot%\system32\dumprep 0 -k
O4 - HKLM\..\Run: [ViewMgr] C:\Program Files\Viewpoint\Viewpoint Manager\ViewMgr.exe
O4 - HKLM\..\Run: [hwbads] c:\windows\system32\ttdrvs.exe
O4 - Startup: Webshots.lnk = C:\Program Files\Webshots\Launcher.exe
O9 - Extra button: (no name) - {6685509E-B47B-4f47-8E16-9A5F3A62F683} - file://C:\Program Files\Ebates_MoeMoneyMaker\Sy350\Tp350\scri350a.htm (file missing) (HKCU)
O9 - Extra button: WeatherBug - {AF6CABAB-61F9-4f12-A198-B7D41EF1CB52} - C:\Program Files\AWS\WeatherBug\Weather.exe (file missing) (HKCU)
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Some of these aren't necessarily bad, just not needed.
Lastly, you DO want to do ALL your tools and cleaners from Safe Mode. And I suggest doing them ALL from EVERY user account you can get in. As each user account can have spyware all its own.
I might also say that this one worries me:
O4 - HKLM\..\Run: [hwbads] c:\windows\system32\ttdrvs.exe
It could come right back as a different name. So watch for that. Scan with HJT as soon as you clean and see if another similar entry shows up. Or log off and back on in Safe Mode and see if one reappears. If so, you aren't clean yet!
Good luck.