In Windows 7, the Vivado installer (Version 2014.1 or later) hangs when installing VC++ runtime libraries, as shown in the following screen capture:
This issue was reported by a user but was not reproducible after the computer being used was rebooted.
From the log files it appears that the MS VC++ install task was starting two instances of vcredist_x64.exe.
To fix this, first open the task manager, and see if two instances of Vivado\2014.1\tps\win64\ vcredist_x64.exe are running.
If so, kill one of the processes.
If this is not the case, kill the hanging process (vcredist_x64.exe) to allow the main Vivado installation to finish, and then re-run the task after the installation has completed.
See (Xilinx Answer 60111) for information about re-running Post Install executables such as vcredist.exe.