Vista - File associations - open with - context menu

I wished to amend a .BAT file, so opened it with OPEN WITH and selected my
editor (NoteTabPro). Now when I double click on BAT files it opens the file
in the editor instead of running the BAT file. I tried changing the OPEN WITH
to cmd.exe, but that just opens the DOS window. How can I set .BAT files to
run correctly? What should I OPEN WIT?? The old (XP) way to change file
associations doesn't seem to have any effect. Similarly, if I right-click an
HTML file and choose "edit", it opens MS WORD; but I want to use my own
editor (NoteTabPro) - how can I change this setting (again, file associations
don't take). I dare not use OPEN WITH !!!!