Got some vim hacks I can share with you. If you want to change the default mode, just edit the script. Now it defaults to {$mode delphi}. I think the .vimrc file of my current installation is around 1500 lines long *phew*. This example script shows two things:
  1. Vim is a powerful editor, that you can customize as you like (almost)
  2. Vim-script syntax is horrible


Code:
function! InsertModeLine()
python << endpython
import vim
unitname=vim.eval("expand('%:r')")
vim.current.buffer[0:0]=['unit '+unitname+';']
vim.current.buffer[2:0]=['{$MODE DELPHI}']
vim.command(":$")
del vim
endpython
endfunc

augroup Delphi
    autocmd!
    autocmd BufNewFile,BufRead *.pas,*.pp,*.dpr :set tabstop=4
    autocmd BufNewFile,BufRead *.pas,*.pp,*.dpr :set shiftwidth=2
    autocmd BufNewFile,BufRead *.pas,*.pp,*.dpr :set softtabstop=4
    autocmd BufNewFile,BufRead *.pas,*.pp,*.dpr :set expandtab
    autocmd BufNewFile,BufRead *.pas,*.pp,*.dpr :set nospell
    autocmd BufNewFile,BufRead *.pas,*.pp,*.dpr :let g:pascal_delphi=1
    autocmd BufNewFile *.pas,*.pp :call InsertModeLine()
augroup END
In short, it sets tabs to be equal to 4 spaces, and sets the auto indent tabstop at 2 spaces. The rest is just for show For some reason vim defaults to some late 60'ies syntax for pascal, but more modern delphi and fpc syntax is provided.

If you want fpc syntax: do this changes
Code:
// Change this line
let g:pascal_delphi=1
// to
let g:pascal_fpc=1