From WebSphere 7, IBM recommend to install all fixes with IBM Installation Manager for WebSphere. However, IBM, for now, still keeps UpdateInstaller for installing the ifixes for WAS7. Although UpdateInstaller can install ifixes for WPS7 through specifing the pak file location, you will not see the installed ifixes in IBM Installation Manager, which is not easy to managment the ifixes.
so I recommend to install WPS7 ifixes (JRXXXXX) using IBM Installation Manager. But, it is slower if you use Installation Manager UI which was installed UNIX platform (must using Xterm) to install an ifix.
Here is the way to install and ifix silently for WPS 7
(1) copy WPS7 ifix to the temp directory, and unzip it. In general, an ifix for WPS7 is a ZIP format file. for example, 184.108.40.206-WS-WBI-MultiOS-IFJR38536.zip
(2) go to the directory /IBM/InstallationManager/eclipse
(3) create a installation response xml file, for example, JR38536_repsonsefile.xml, the content should be like this and change the necessary fields. see the bold type character