Is there a way (or plug in) that adds a set of predefined custom fields to be filled in specific types of post or pages?
If I have a category, "Gallery", set up and I create a new post for that category.. how can I have the custom fields "Height", "Width" , "medium", "date" , and "Image" be created automatically ( currently I have to manually create 5 new custom fields and scroll down from the pull down menu to select the appropriate field name each time I create a new post, which is not very efficient.
Any suggestions would be greatly appreciated.
You can add and define metabox info for a post type by using Easy Custom Content Types by Pippin's Plugins. He's a solid Plugin developer who follows best practice in coding and is very good at supporting his products. I own this and have used it to heavily customise an academic post entry with multiple extra entries. I wouldn't hesitate to recommend it and it should be easy enough to estabilsh if it will do what you need to before purchasing as well.
It's quite simple to do, actually. Here's a good tutorial to start with: http://wp.smashingmagazine.com/2011/10/04/create-custom-post-meta-boxes-wordpress/
If you prefer a plugin, then something like WPAlchemy might be a good option. The developer also has a tutorial on how to build custom meta boxes without using the plugin: http://www.farinspace.com/wordpress-meta-box-next-level/