Superman Adventures was a DC comic based on the animated series continuity rather than the standard series of the time (Superman, AoS, MoS, MoT, etc.). Artwork and plots were similar to the animated series, and it was primarily intended for younger readers -- fans of the show rather than the comics.
From what you say about it being a magazine rather than a comic, I wonder if what you are talking about is a British reprint of the original DC material; there is a "tradition" here of doing that which may stem from distribution problems with the US comics -- plus the chance to make money from UK-based advertising.
SA wasn't bad as a comic and as related material to STAS (though I shall not bore you with my objections to the show), and ran for a few years after the series ended. It was cancelled when the Justice League series was made and replaced by a JL-based comic. I'd give more details but my copies are packed away at present.
