Christine, resize to a slightly larger image than required, then use the crop tool. This is how I do it.
I assume you have downloaded the latest criteria for passport photo and also seen the very high percentage of home "processed" images that have been returned as unacceptable.
Having said that all recent photo's of my family where accepted without any problem.
http://www.passport.gov.uk/news/news...ntelement=1008
http://www.telegraph.co.uk/news/main...passport14.xml
Harry