"Well, everything worked fine until you installed that [Chrome | Firefox | Opera] thing on my computer." Doing free tech support for non-technical people is a wonderful thought, but it can also provide a harsh lesson in the dangers of unlimited liability for open-ended, no-fee, no-contract work.
My sister still gives me the "my computer runs slower now" after I had her do IE9.
Personally, I just take the opportunity to work on my sells skills. After all, IE9 is only a Microsoft blessed upgrade.
My mom asked about Chrome because she saw a Google ad. Let's see if I can "sell" her on it. Keep up those ads Google.