How do I remove InstallMac from my browser's homepage and default search?

How to  remove "InstallMac" from Safari's homepage and default search
First you must uninstall it. <This link is a direct download>
Please read carefully  the following step by step  tutorials:

1. Click on Safari, located in the upper left hand corner of your screen.
2. When the drop-down menu appears click on Preferences....
3. Safari's General Preferences should now be displayed, overlaying your browser window.

To modify the address of your home page, enter the desired URL in the edit field provided. To modify the search click on Default search Engine.

If you would like to set the current Web page as your home page, click on the button labeled Set to Current Page.

To remove from Firefox and to change the default search please follow these instructions:

1. Type "about:config" into the address bar and click "Enter".
2. Click the "I'll be careful, I promise!" button.
3. Type "keyword.URL" into the search box that appears.
4. Right-click on the "keyword.URL" entry and click "Modify"
5. Delete the text in the box and click "OK"