Maxigallery will do just about anything you want. This snippet call will show just the thumbnails but clicking on any of them will show the larger picture (with previous and next buttons to browse through the larger pictures):
<h3>Click on a photo to see a larger version</h3>
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<p>
[!MaxiGallery? &display=`embedded` &embedtype=`slimbox` &pics_per_row=`3` &max_thumb_size=`110` &admin_webgroups=`wugPhotoAdmins` &manager_webgroups=`Photo Admins` &max_pic_size=`480` &thumb_use_dropshadow=`1`!]
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Members of the two groups will see a "manage photos" button on each gallery page that will allow them to upload, delete, caption, and remove photos. This is a barebones MaxiGallery setup. You can do a lot more styling using tpl parameters.
Remember that all the Maxigallery effects (e.g. dropshadow) and sizing take place on upload so when you change things, you have to re-upload the pictures to get the new effects. Remember, too, that the parameters are enclosed in backticks, not single quotes.