>2. Every time I hit <C-s> Vi freezes immediately (have to close the >window). I tried to unmap it with "map <C-s> <Nop>" and "map! <C-s> ><Nop>" and tried to map it to something different with "imap <C-s> ><ESC>:w<CR>i" but nothing helped.
^Q/^S (DC1/DC3) are terminal xon/xoff characters, respectively, typically used to momentarily pause output so that the recipient can "catch up". Also comes in handy to slow screen output so you could read it before it goes whizzing on by. Another ^S could be used to "restart" the screen if xon/xoff is in "toggle-mode", else just hit ^Q to restart it for sure.
