Actually all the R1 entries in HJT point to the same
estpl.dll/sp.html#93256
Here is the complete R1, R0, R3 logs now
R1 - HKCU\Software\Microsoft\Internet Explorer\Main,Search Bar = res://C:\WINDOWS\system32\estpl.dll/sp.html#93256
R1 - HKCU\Software\Microsoft\Internet Explorer\Main,Search Page = res://C:\WINDOWS\system32\estpl.dll/sp.html#93256
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Default_Page_URL = about
:blank
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Default_Search_URL = res://C:\WINDOWS\system32\estpl.dll/sp.html#93256
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Search Bar = res://C:\WINDOWS\system32\estpl.dll/sp.html#93256
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Search Page = res://C:\WINDOWS\system32\estpl.dll/sp.html#93256
R1 - HKCU\Software\Microsoft\Internet Explorer\Search,SearchAssistant = res://C:\WINDOWS\system32\estpl.dll/sp.html#93256
R0 - HKLM\Software\Microsoft\Internet Explorer\Search,SearchAssistant = res://C:\WINDOWS\system32\estpl.dll/sp.html#93256
R1 - HKCU\Software\Microsoft\Internet Explorer\Main,Window Title =
http://www.yahoo.com
R1 - HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings,ProxyServer = 192.168.0.153:8080
R3 - Default URLSearchHook is missing