Extremely basic, how to get started stuff.
I have to admit, this does seem pretty trivial, but when I was first playing with Seaside, I had a number of false starts due to downloading images loaded with out-of-date versions of Seaside. I got Ramon Leon's image (which he's since updated) and that worked well, except it tried to load various Windows fonts (on my Mac) on every boot.
Of course the reason all this is possible is that Smalltalk gives you a lot of options for customization. You could even say Smalltalk is a large set of options for customization. Due to the whole "virtual machine" thing, it's almost more like using Parallels than like using Dr. Scheme. Even Eclipse doesn't come close, which is ironic given Eclipse's strong historical link to Smalltalk. (I think Eclipse even started out as a Smalltalk implementation.)
But all those options can be a bit confusing first time out. So, remember, if you're a Seaside newbie, this is the Squeak image you want to use.