The auto-indent is based on the current syntax mode. I know that if you are editing Foo.java, then entering a {
and hitting Enter indents the following line.
As for tabs, there are two settings. Within Vim, type a colon and then "set tabstop=4" which will set the tabs to display as four spaces. Hit colon again and type "set expandtab" which will insert spaces for tabs.
You can put these settings in a .vimrc (or _vimrc on Windows) in your home directory, so you only have to type them once.