Son in Law was certainly a lot funnier the first time I watched it although I was younger then. And although I think it could be a mix of me maturing as well as being able to predict everything that happens, Son in Law was not as good this time around./
The plot in Son in Law is ridiculous. It rarely even attempts to disguise the fact that it has no meaning, and this would be ok except that it means that the comedy all centres around Pauly Shore without much of a comedic premise. The idea of contrasting country life to the lifestyle of the youth in California College has a humourous anecdote to it even if it's a little bit familiar, but at heart there is really no central premise. The story doesn't exactly matter because the film is mainly a comedy sketch stretched out to feature length more than a general film and in that retrospect, but still it just doesn't have much thought to it and is left to be rather bland. The script doesn't exactly have all that much heart to it, and so if viewers don't laugh then there is really little else of value whatsoever in Son in Law. The scenery of the film is nice and has plenty of colour to it, but the story is a shallow and generic one which has been told a countless amount of times in other teenage films with slight alterations, with many of the other films being better and worse.
The general atmosphere of the film is nice though because it does manage to achieve a realistic country town feel thanks to the nice scenery of the film and the soundtrack, and all in all Crawl is a likable character which means that audiences who find him funny are likely to find themselves cheering for him as he seeks the approval of the Warner family. The entire film is a light hearted experience and is a rather easy film to watch, and despite the familiarity of the experience it has some certain themes to it which make it touching in a slight manner.
All the importance in Son in Law rests on the performance of Pauly Shore. The film is built on his over the top comic persona in the role of his alter-ego "The Weasel", and for the most part he succeeds. Occasionally the gag gets rather silly and feels somewhat unnecessary in the context of certain lines, but when the script really calls for it he steps up to the plate and delivers what is needed. He cuts loose and lets the Weasel work his magic, and even though he doesn't really have a comedy partner to work with and is reliant on carrying the entire film on his shoulders, he manages to put his energy into the part which makes him an entertaining presence. As a character surrounded by a world of stuck up dramatic people, Pauly Shore stands out as Crawl due to his lighthearted approach to all the situations presented to him and the physical attire he is decked out in a zany costume. Pauly Shore is a genial presence, and although the film around him may not present enough situations for him to truly soar as much as he could, he does his part to ensure that his fans are pleased with the amount of laughs he brings on board. Pauly Shore manages to make Son in Law a mostly worthwhile front for his comedic talents, and so he easily makes himself out to be the best aspect of the project.
Carla Gugino does a decent job as well. Even though her character is a thinly scripted figure who is really there only as the archetype that reveals how a girl changes to a woman when she goes through college, Carla Gugino's natural charm manages to make her a consistently likable character. She has a nice chemistry with Pauly Shore, and although she isn't exactly that funny, she makes a good duo with him and ensures that the story at least manages to achieve reaching some form of meaning to it. Carla Gugino does a decent job in Son in Law.
Patrick Renna does a decent job as well because he manages to create strong comic chemistry with all the actors that he interacts with the surrounding cast. He plays the annoying little brother archetype fairly well with a comic interaction with Carla Gugino and his friendliness with Pauly Shore. He manages to make himself an entertaining foil in his supporting part simply because he plays the part well with his naturally childish charisma. He makes a decent addition to the cast.
Cindy Pickett makes a good mother figure because of the chemistry she shares with Carla Gugino, the way she delivers her lines in the script with a serious understanding of what she is saying and the fact that as she proved earlier in Ferris Bueller's Day Off, she is able to portray the mother archetype very easily with a naturally likable appeal to her.
Lane Smith makes a good father figure as well, and Mason Adams makes himself a decent addition to the cast as the grandfather of it all.
Tiffany Thiessen small role is also a decent touch because the film plays on her sex appeal well in one key scene.
Lastly, Brendan Frasier's cameo is a nice touch for anyone who is a fan of his leading performance in Encino Man.
So Son in Law is a strictly Pauly Shore fare. It doesn't have him teaming up with anyone especially funny this time so it doesn't reach the same level of entertainment value that he got in Bio-Dome or Encino Man. But for what it's worth, he makes an entertaining lead and fans of his should find the film to be a mostly entertaining venture as it's good for a few laughs at the least.