hi can anyone tell me what files are suitable for a mac? sit rar zip and so on. thanks

.sit and .dmg are mostly created by and for macs.

quicktime usually has no problems with .mpg's, but .mpegs are less likely to work.

What are .rar and .iso and are they downloadable to OSX. Thanks!

.rar are usually files that have been segmented (like a DVD broken into smaller chunks). Stuffit can usually handle them OK.

.iso is another disk image format usually seen on PC's.

Look to waste a lot of time and bandwidth with both formats, on OS X.

google could probably help your specific situation better. For starts, look here http://www.xbox-scene.com/articles/macosx.php