Vim autoindenting?

Does anyone else find gVim 6.4 a bit unstable on Windows XP? It’s
become my editor of choice since learning it recently but I’m noticing
some peculiar behavior. Last night I spontaneously lost the “Edit in
vim” context-menu option, at the same time as its autoindenting feature
changed on its own.

So I can confirm what’s going on, what options control the
autoindenting?

The behavior I want is for it to indent two spaces after I type
something like

x = Fred.new(
indent like this.

and hit Enter.

What I’m seeing is that it indents to the point of the open parenthesis.

x = Fred.new(
indent like this.

I’m not sure what options govern this or why it changed, because it was
behaving properly yesterday and I haven’t altered the _vimrc options.

Thanks,
Jeff