This site will look much better in a browser that supports web standards, but it is accessible to any browser or Internet device.
First, upgrade to Internet Explorer 6. Most sites that try to hijack your search engine will now trigger a 'do you want to do this' warning message that helps you prevent search engine hijacking and home page hijackings (and 'hidden' background install of spyware).
Go to IE tools, internet options, programs and use the 
					option to reset the IE defaults. Reboot.
					
					If that doesn't work, shut down IE and search for a *hidden* 
					file called HOSTS (hosts.sam and lmhosts are sample files 
					but are occasionally used in error). HOSTS is effectively a 
					redirection file. Rename HOSTS to HOSTS.OLD -or- open using 
					Notepad and remove any reference to the problem site/s 
					(place a # at the beginning of the line or delete the line 
					in its entirety).
					
					Go to IE Tools, Internet Options, Accessibility. Make sure 
					there is no style sheet chosen (under User Style Sheet - 
					format documents using my style sheet). If the option is 
					turned on, turn it OFF.
					
					You may also need to delete the following registry keys:
					
					HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer\
					Main\Search Bar
					
					HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer\
					Main\Search Page
					
					HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer\
					Main\Start Page
					
					HKCU\Software\Microsoft\Internet Explorer\SearchURL
					
					HKCU\Software\Microsoft\Internet Explorer\Main\
					Default_Page_URL
					
					HKCU\Software\Microsoft\Internet Explorer\Main\
					Default_Search_URL
					
					HKCU\Software\Microsoft\Internet Explorer\Search\
					SearchAssistant
					
					HKCU\Software\Microsoft\Internet Explorer\Search\CustomizeSearch
					
					HKEY_LOCAL_MACHINE\Software\Microsoft\Internet Explorer\
					Main\Search Bar
Follow the advice at this
					troubleshooting 
					link to see if you can track down what is changing your 
					search engine options. 
					
					Once you are sure that your system is clean, try resetting 
					IE's defaults again. 
					
					Make sure you have not been hijacked by a virus or trojan. 
					Run a full virus scan using an up-to-date antivirus 
					programme, and if it is your problem PLEASE update your 
					version of Internet Explorer:
					
					http://support.microsoft.com/support/kb/articles/Q275/6/09.ASP
					
					
					Adult content web site is unexpectedly displayed in browser 
					window when you click on search
					
					http://support.microsoft.com?scid=kb;EN-US;Q323869 
					
If, despite your best efforts, you have no luck AND you 
					have MADE SURE that you have not been infected by a hijacker 
					or virus, you can click on a link to download a zip file 
					containing a txt file. Have a look at the text file to 
					reassure yourself as to the contents, then change the 
					extension of the file to reg. After you have made that 
					change, double click to merge the file with your registry 
					(or single click if you have that enabled on your system) - 
					make sure you also follow the troubleshooting advice above, 
					or you will have to repeat your repairs.
					
					Make sure you know how to backup and restore your registry 
					first.
					
					IE4 
					defaults
					
					IE5 
					defaults
					
					IE6 defaults 
					(Windows 2000 and up)
					
					IE6 defaults 
					(for all operating systems)