How Does a Friend of Mine get Rid Of http://isearch.claro-search.com from his PC......?

I would suggest using "Hijackthis" Hijackthis

Do a scan and save the logfile. Go to the webpage www.hijackthis.de... and copy and paste your entire logfile. This will show a list of hidden startup files, web browser addons etc. I bet you any money your virus will have entries here. Anyway.. check all the user entries posted on that website after you post your logfile and remove any entry that is considered nasty.

BE CAREFUL THOUGH.... as getting rid of certain files can mess up your system. Be certain the entry is nasty and check each one carefully to get rid of them.