OMG Deb i cannot imagine jam and marmite together - urgh making me sick thinking of it...
you have to ease yourself into marmite (vegemite is a milder taste IMO) so in the beginning when Dh gave me some (12 years ago) i had tons of butter and a tiny bit of marmite. almost spit it out. the second time i liked it better and by the 3rd time i was hooked. when i brought it with me home to the states at one point my family could not stand the smell or anything to do with it, but my mom's cat was in heaven and if the jar got opened she would come running from wherever she was hiding - must be like catnip for her
it IS loaded with vitamins though so is great to give as a simple food for kids - toast/bread with butter/marg and a smear of vegemite/marmite. some people add it to soups and casseroles as well.