different pens for different uses:
for day to day notes to myself and the like, i use a namiki retractible fountain pen, medium nib.
for simple letters and notes, i use either the namiki, or a schaeffer fountain pen, wide nib.
for a slightly fancier touch, i'll break out the mont blanc, wide nib, but not often.
at work, just about any disposable pen with wet ink will do. pilot makes some nice ones. no rollerballs for me. sharpies are for kicking people out, and making notes throughout the night.
i always use black ink. can't stand to see my writing in any other color. for letters and correspondence, i use a gold colored parchment paper and a read wax seal pressed with the image of a dragon.
it's a shame that in this computer era, the art of the letter is being lost. there are few things that i enjoy more than the scratch of a nib across parchment, carefully writing to avoid wet ink, writing slowly and deliberately so you don't make errors that you can't erase, and melting the wax for the seal. i love sending letters, and i love getting letters.