Means she'll be taking alot of pictures inside and out of the ship.
Check the review here: Canon PowerShot G7
, IXUS 900 Ti
Check this one as well: F31 fd
Older model that base upon: F30
Try the cameras at the store before you buy, It would give you feel of how comfortable they are to use. And check the parts availability and cost of having optional hardware like extra memory cards, and battery if comes a time to replace them.