OK now you have to edit your HOSTS file and remove entries that you didn't create.
This is a copy of mine it has no changes Vista may be slightly different (I have XP Pro).
# Copyright (c) 1993-1999 Microsoft Corp.
#
# This is a sample HOSTS file used by Microsoft TCP/IP for Windows.
#
# This file contains the mappings of IP addresses to host names. Each
# entry should be kept on an individual line. The IP address should
# be placed in the first column followed by the corresponding host name.
# The IP address and the host name should be separated by at least one
# space.
#
# Additionally, comments (such as these) may be inserted on individual
# lines or following the machine name denoted by a '#' symbol.
#
# For example:
#
# 102.54.94.97 rhino.acme.com # source server
# 38.25.63.10 x.acme.com # x client host
127.0.0.1 localhost
You can use hosts file protectors, though personally I have never felt the need.
You may have other stuff on your system so these would also help.
If you haven't already got this software (freeware), download, install, update and run it,
preferably in safe mode and report the findings (it should product a log file).
1.
SUPERantispyware On-Demand only in free version.
2. MalwareBytes Anti-Malware, On-Demand only in free version
http://download.bleepingcomputer.com/malwarebytes/mbam-setup.exe, right click on the link and select Save As or Save File (As depending on your browser), save it to a location where you can find it easily later.