While it's glorious in many ways to have movies and TV shows available on DVD, it's worth noting once again that sometimes consumers are getting just half a loaf in their purchases.

I'm not just talking about the practice with some TV series of splitting single seasons into multiple DVD sets. Two examples arriving from CBS/Paramount on Tuesday: Cannon: Season One, Volume One (12 episodes, four discs, $39.99) and Jake and the Fatman: Season One, Volume One (11 episodes, three discs, $40.99). That's unfortunate enough, especially when the shows involved are milking money from viewers in their fixed-income days; Cannon, for one, first aired more than 35 years ago — and was a hit with older viewers then.

But the problem goes beyond how many shows are in a package to the way the shows are presented. It's that you may not be getting the show you remember.

As I mentioned in last week's DVD column, music-rights issues have caused considerable problems for some shows going to video, since DVD distributors don't want to have to pay big bucks to license the music that was part of an original telecast.

The Wonder Years and China Beach are two shows said to be stuck in DVD limbo because of music rights. In other cases, other music is substituted, even though the original tunes were carefully tied to what you were seeing.

The new Jake and the Fatman DVD bears a note that ''music has been changed for this home entertainment version.'' You may not think of that 1987-92 series in terms of its soundtrack, but the fact is that music can be part of our memory, consciously or not. Hence the brouhaha mentioned a week ago over the changes in the soundtrack to The Fugitive.

I wasn't a fan of Fastlane, the 2002-03 Fox series that is arriving on DVD Tuesday (Warner, 22 episodes, six discs, $59.98). But I remembered its flashy visuals and blaring soundtrack well enough to think something was wrong with the music when I revisited it on DVD. Sure enough, there's a terse acknowledgment that ''some music differs from the original televised version.''

Then there's the issue of whether shows are being presented in their original network form or in versions edited down later for syndication or cable. More often than not, DVDs try to go back to the network forms, but you can't always be sure, and distributors don't always enlighten you, or do so in a vague way. CBS/Paramount has taken to covering itself with a pro forma note — visible on both Cannon and Jake and the Fatman — that ''some episodes may be edited from their original network versions.''

All this leaves a consumer in a quandary. If you really love Cannon, will you take a modified version — especially if that's the only way you're going to get it? Is a Wonder Years with music substitutions better than no Wonder Years at all? And how much would you pay to get it with all the music intact? Would that buyers were given a chance to make the packaging decisions.

Consumer tie-ins

With a new, big-screen version of Journey to the Center of the Earth due on Friday, Genius Products is releasing a recent TV-movie rendition of the story on Tuesday for $19.98. The TV production stars Peter Fonda and Rick Schroder. At least, the movie's credits call him Rick; the DVD box still tags him as Ricky.

The big-screen Journey stars Brendan Fraser, who on Aug. 1 will be back onscreen with The Mummy: Tomb of the Dragon Emperor. In case you've forgotten Fraser's earlier Mummy movies — or lost your old DVDs — Universal is releasing Fraser's The Mummy and The Mummy Returns in two-disc ''deluxe editions'' combining new extras with ones from previous DVD versions. Each set lists for $19.98. Blu-ray versions, at $29.98 apiece, will follow on July 22.

A two-disc edition of the original The Mummy with Boris Karloff also arrives Tuesday, for $19.98.

Also on the product-promotion side is The X-Files: Revelations (Fox, eight episodes, two discs, $22.98). The sampler of episodes from the show's first six seasons is being presented as an ''essential guide'' to the new The X-Files: I Want To Believe, due in theaters July 25. The subtext is that it has been six years since the series ended and 10 since the first X-Files movie, so some people may need to catch up.

Not hard-core fans, of course, but they're going to buy this for the new episode introductions by series creator Chris Carter and producer Frank Spotnitz, not to mention the half-hour of Q&A with Carter, Spotnitz and stars David Duchovny and Gillian Anderson, recorded at the WonderCon convention in February. There's also a trailer for I Want To Believe that was unveiled at WonderCon.

I didn't catch any hot news about the movie in the extras, but they do serve as a good primer for the show, and a reminder that it was at times very funny, it could do self-contained stories and it liked to scare the daylights out of viewers.

Since my DVD package didn't say which episodes are in the set, here's the list: the pilot, then Beyond the Sea, The Host, Clyde Bruckman's Final Repose, Memento Mori, Post-Modern Prometheus, Bad Blood and Milagro.

Funny business

Superhero Movie: Extended Edition (Genius, $29.98) offers seven more minutes of slapstick and parody than the 75-minute theatrical version, along with other extras. 305 (Allumination, $29.99), meanwhile, offers a feature-length expansion on the online parody of 300; the original five-minute short — included among the DVD extras — is just a launching pad for the comedy. And it made me laugh, perhaps because it so often feels like an extremely weird episode of The Office.