Hi Keith,
If the photo you upload is just a thumbnail then it will not be possible to resize it to a large version (well it would look horrible if you managed it).
Did you upload them as attachments or in to your gallery?
In both cases I would advise uploading them at the maxium size it allows. The attachments method will then automatically show a thumbnail which the user can click on to see the full version. The gallary has a thumbnail method to add to your posts I believe.
Pictures can automatically be downsized to thumnails by the software, but if they are uploaded as thumnails then there is just not enough information within the pic to enlarge them again.
Take a look at our tips links for photos.
http://www.orchidboard.com/community...chidboard.html