New to digital photography

[Clive]

A simple and probably stupid question. Can I use the same type of
filters which I used with both black & white film and colour with a
digital camera? (Canon EOS 350D).

[Al D]

Yes, but be aware that, especially if you're intending to reproduce the image as black & white, you may not get quite the same effect, but that's more from digital quirks than anything else. And shut off your white balance, or lock it before attaching the filter.

[Zeitgeist]

yes but in most cases unnecessary.

IE: warming filter, which was actually unnecessary in the film days unless
you shot slide film in the shade and in fact just sucked up .1 of a stop for
no reason.

red, yellow and green filters for tonal shifts of sky, foliage, skin tones
can all be done in photoshop, in fact now you can sellect which filter to
use later without loosing the one or two stops.

softfocus, instead of embedding it permanently in your image you can
selectively soft focus effect in photoshop and blend the layers as you
prefer, varying the strength overal and in specific locations at will.

other special effects, prismatics, stars, diffraction, vignetting ...
photoshop it.

polaroid filter seems to be the only one that can do things you can't do
better in post.