Generating hierarchic URI's based on taxonomy
From the comments, this is one way how I would do this:


create a taxonomy vocabulary called gallery type.
create a taxonomy vocabulary called year.
populate them with the appropriate terms.


Then I'd create a view:


filter it on gallery type (or whatever content types are tagged by the above vocabs)
also filter it on all nodes that are published


In arguments (d6) or contextual filters (d7) I'd put in two arguments.  They would be taxonomy terms and you can select them from the dropdown list from taxonomy:


For the first, select taxonomy term and then in validation, select taxonomy and term again and restrict it to the gallery type vocabulary. 
For the second select taxonomy term and then in validation, select taxonomy and term again restrict it to the year vocabulary.


Then, in the Fields, select whatever fields you want displayed.  For ease here, just select node title, but once in production I'd imagine they'd be title, a picture or image or two, a description, etc.

Now, create a page display in the view, and in the path enter

myfirstview/%/%

Change myfirstview to whatever makes sense on your website's hierachy.  What the two %'s do is substitute in the taxonomy terms above.

Save everything.

Now you have created a View that does all that hierarchy for you.  So, if someone goes to...

www.yourhost.com/myfirstview/movies/2009

...Views will create the page for you and display the title of whatever content has been tagged with both movies and 2009 (views takes the hardcoded myfirstview and substitutes in the movies and 2009 and then matches them against what content is tagged with those terms) and if they went to...

www.yourhost.com/myfirstview/pictures/2012

...Views would create a page of all pictures from 2012 doing the same logic.

What is nice is that you can then create a views that filter on only one of the vocabularies, eg,

www.yourhost.com/mysecondview/pictures

that would list all pictures

or

www.yourshost.com/mythirdview/2012

that would list all content from 2012

As you get more comfortable with Views you can then add all kinds of different sortings, eg, sort by posting or last edit date, sort alphabetically by title, etc, but this should get you on your way.  Just play around with the settings and hit Preview a lot.  You'd be amazed how simple it is once you get past the up front daunting nature of all the various options you have.