two things: have any of you upgraded to leopard or snow leopard. if so, do you by any chance use CS3. how have CS3 and plugins been impacted. also, is anyone using a version of paintshop pro for mac? there seem to be some wonderful things you can do in there.
CS3 is sadly neither tested or supported in Snow Leopard and Adobe say they aren't going to either. Bit harsh of them but there you go. CS4 works fine apparently in the new OS.
@ yellowdog07
"is photo filtre mac compatible?" Apparently not.
Start with iphoto. It is included with your mac. It is a photo management program that has some useful editing features. To re-size you will have to choose export in the file menu.
or-
To resize only - just double click the image file to open in preview and choose adjust size from the tools menu.
For any serious editing and such the GIMP is excellent free software as tealeaves has linked below.