As a cave crawl, Spelunker's Quest is rather typical for the genre, although in this case, more is definitely less. The charm of Adventure was its lack of specificity. Because you never knew exactly why you began outside the building, you were free to create your own backstory. Spelunker's Quest (SQ) however, provides you with a plausible backstory, and then fails to use it; it exists simply as a vehicle to get you to the initial room.
The gameplay itself is typical for the genre; there are monsters which mean multiple opportunities for sudden death. The objectives -- getting treasures and getting out -- also break no new ground, except that they're less plausible than usual. Why is that? The backstory gives you a reason to escape, but not a reason to collect treasure. The puzzles themselves aren't terribly difficult, except for two; one involves random violence for no particular reason, and another you'll probably discover through just plain dumb luck. These two puzzles cause the playability to suffer a notch or two.
SQ provides fairly evocative room descriptions, decent descriptions of objects, and doesn't bother with implementing much else. This approach can leave you playing the "get all" game to see what objects are available. Stylistically, you'll find single-line responses with exclamation points and droll replies, again evoking the early cave crawl games. However, the objects and their uses betray that spirit. SQ features both modern and ancient weapons, both technology and magic, without any real thought behind how all of these work together -- it's like the items are present just to solve puzzles.
Finally, while SQ can be solved in thirty minutes or less, you're left with a feeling of incompleteness all the same. How exactly did such a strange world exist in the first place, cobbling together elements from many different times and places? Would your friends believe you when you told them? Isn't there, or shouldn't there be, more? As for a little bit of fun, SQ suffices, but it leaves you with a bland kind of fun, like eating aged cereal.