I used CMS Made Simple, completely free, for one site and it worked out pretty well. It’s a nice product for a brochure-ware type site….here is the site.
http://www.atrafireplaces.com/
It builds all those drop down menus internally. etc…...lots of add-ons also.
This was a well paying client - but they had no need for the more technical and changeable features of EE. The site has remained the same for over a year/
Edit - not sure of what their gallery or portfolio features are…...
I also recently used Gallery (free script) for my large picture gallery…...
I have to go with Handyman on this one. CMS Made Simple was a breeze to set up and modifying an existing theme to suit your needs is quite simple. I was able to set it up, re-skin an existing theme, and migrate a clients static site content (about 10 pages) in about 5-6 hrs (with no prior experience using cms made simple).
The Gallery add-on is great. Puts a Gallery module in the main admin and you can upload multiple photos at one time. I believe it generated its own thumbnails as well… It allows you to choose from 3 (i believe) delivery methods, Lytebox, ThickBox, and a few others.
All in all a great opensource product.