To delete things in vi switch to command mode (press escape) navigate to the thing you want to delete and press x. Should work for any character including whitespace. You might want to go over the tutorial that comes with vim (run vimtutor).
Emacs also has a tutorial, press C-h t (that means hold control and type h, then release control and type t). #abc.c# looks like an autosave file. To compile:
to run any shell command use M-!. (M is for Meta which is probably alt on your keyboard).
