as a rule of thumb is there any Font which works & looks better for subtitle .
is there any difference in applying a font as far as progressive and interlaced footage are concerned . TIA.
Keep to sans serif fonts - they tend to view better on screen, IMO. With interlaced footage, a serif on a font can get lost on alternate fields and cause the subtitle to appear to flicker.
I have no idea... when you watch a film, what font does it look like to you?
I'd stick to the advice I gave above - but play with different fonts to see what you can do. I tend to use Helvetica, which comes out fine for what I do.