One could debate a lot about the respective merits of the film Jurassic Park. It’s widely considered a classic, but upon observation, some things might be slightly lacking.  Don't get upset: it's just a possibility.
But with The Lost World, you really don’t have to look that hard. 

  Plot: It’s been a few years since Jurassic Park had its major PR disaster. John Hammond inexplicably wants to send a team of people to his second Jurassic Park island to protect the dinosaurs that are inexplicably still surviving there. He inexplicably tricks Ian Malcolm into going by sending his paleontologist girlfriend ahead of him. Ian inexplicably, accidentally(and highly negligently) brings his daughter on this EXTREMELY DANGEROUS AND POINTLESS MISSION TO DO NOTHING. Then later they go home and a T-Rex escapes and roams around California, and it, too, is kind of pointless and inexplicable. 
Nothing But Trouble This movie is so full of problems, it’s hard to know where to start. Can I say that this movie has anything going for it?... I suppose it has dinosaurs in it. That’s about it. 

Pictured: Dinosaurs. But even they aren't very appealing looking.
Plot Mess The plot is hideously messy — and I don’t mean that in a “dinosaurs tearing people apart” sense, but in a “this movie didn’t seem to understand how plots work” sense.  The reason people return to the island feels very feeble — you just can’t get it out of your mind that “just figuring out why the dinosaurs haven’t died despite being bred to be lysine deficient” ISN’T A GOOD ENOUGH REASON TO SEND A TEAM OF PEOPLE IN HARM’S WAY. Makes millionaire John Hammond seem like kind of a thoughtless jackass who learned nothing from his experiences in the first film.  There are people in this movie.
...They mostly don't look like actors.
For another thing, the movie feels like it’s over about halfway through — when our heroes escape plunging over a cliff — but it just keeps going. That’s when OTHER people arrive on the island and we’re treated to another inexplicably large and extremely unattractive group of people — none of whom feel like real characters, and none of whom we like or care about. They spend a lot of time milling around and playing with dinosaurs.  
There’s a segment in this part that really captures the ultimate problem with the movie. We’re treated to that one guy from Fargo being attacked by the new star dinos for this film — the “compy”. Well, he’s attacked by a group of them and scares them away. Then he walks ten feet further away — and they chase him down and kill him. It’s a really long and strange segment, because a) we don’t know who this guy is. B) We don’t care that he’s being attacked by dinosaurs. C) I guess we’re supposed to see this as some kind of ironic justice because he was mean to one of the little compies earlier, but it was such an insignificant moment between unimportant, dull characters — who even remembers? So the scene just comes across as (as I said) long and strange, and oddly mean, like Steven Spielberg was really enjoying seeing this character killed in a horrible way. This isn’t Dennis Nedry from the first movie (a slimy jerk who put everyone in harm’s way so that he could make a quick buck) — this is JUST SOME GUY. Why are we reveling in his torment? 

He came from nowhere and went to nothing, and was really ugly, boring and unappealing in the meantime. AND THAT IS THIS MOVIE IN A NUTSHELL. 

Pictured: Compies attacking a small child. In later editions of
the film, they have all been changed into cell phones.
Okay, to get back to the overall plot — the movie feels like it ends AGAIN 2/3rds of the way through when our heroes (and antagonists) finally escape the Jurassic island to make their way back to the mainland — and YET THE MOVIE GOES ON. That’s when we get to the reason the movie was made — getting to see a dinosaur rampage through a modern city. (Well, I guess, if you want to be technical, the real reason that this movie was made was that Jurassic Park made a billion trillion dollars and so a sequel was rushed out as hastily as humanly possible. Which always means you’re going to get a quality product, right?) The dinosaur rampages… and then is pretty easily defeated (if you call “getting to go home scot-free” a defeat).  
Characters The very first problem with this movie is that Ian Malcolm is the protagonist. Don’t get me wrong — I enjoy him in the first movie. But the problem is, his character is only strong enough to be exposition/comic relief — like he was in the first movie. The very first shot of him in this film, he’s yawning (Spielberg tried to pull an Alfred Hitchcock and cut from a woman screaming to Ian Malcolm yawning. I’m sure this moment had good intentions, but it comes across as a very lame visual joke. Regardless…) this sets the tone for the entire film — inappropriate and boring. Ian Malcolm, after coming across as very smart, attractive (in a heavy-handed, sleazy kind of way) and cool in the first film, in this film looks as though he hasn’t slept in a week and has nothing fun or interesting to say. The only thing I can say in his defense in this movie is that he apparently drives a nice car and apparently has no issues with miscegenation. And the weirdest part of all is, after they leave the island 2/3rds of the way through the film, it’s hard to think what else he does in the movie besides delivering a couple smug one-ups near the end of the film. It’s like the movie forgot he was the lead character. 
 In fact, nobody in this movie really feels like the lead character — it feels like a film full of supporting characters with no clear focus on the lead. 
They seemed at one point to be setting up some kind of conflict between Ian Malcolm and his daughter… which develops into big fat nada. They seem to be setting up some kind of conflict between Ian and his unlikeable girlfriend (her being unlikeable is also a large problem, since she’s the female protagonist) — and this also develops into precisely zilch. They seem to be setting up some kind of character arc for John Hammond’s son/stepson/son-in-law (I don’t know which he was and don’t remember his name — the British guy who looks like Bob Balaban, okay?) — and, although it seems to pay off at one point, he also ultimately learns no lessons and (outside of being eaten by a dinosaur) ends the movie pretty much where he started.  
Vince Vaughn is in this movie. I don’t know why, because he doesn’t do a whole lot, and disappears 2/3rds of the way through the film. 
Only one person in the team feels like an actual character — a big game hunter with an extreme facial bone structure — who is also the only person with an arc. 2/3rds of the way through the movie, he discovers he’s “had enough death” or something like that, and goes home. (In other words, he was a character with a clear goal that he set out to achieve — but, in the course of the story, he realized that while he could achieve it, he had no desire to do so. In other words, the story advanced for this character). AND HE, THE ONLY CHARACTER WITH AN ARC, IS NEVER SEEN AGAIN AFTER THAT POINT IN THE STORY. 

Visuals
I'd also like to take the chance to just say -- the visuals in this movie are ALSO extremely unappealing. When I think back to the colors this movie evokes in my memory -- all I have in my mind is a dark, muddy mess. 

Maybe this movie would be better if I just closed my eyes?
Actually, I'd probably get the best results if I plugged up my
ears as well.Ultimately...This is a bad movie. Tonally it's a mess, character-wise it's a mess, and story-wise -- it's a mess. It's even visually unattractive. It comes across as a badly-thought-out cash-grab that Speilberg purposefully made ugly and terrible because he didn't want to be doing a sequel. I'm sure you've already guessed it, but my final pronouncement is...
NOT RECOMMENDED