Pyaar to hona hi tha ("Love had to happen") is a well-done, very close remake of Lawrence Kasdan's French Kiss for an Indian audience. As such, it's an enjoyable, lightweight, fluffy, if inconsequential comedy which, despite its sometimes garish use of colours certainly has its moments and is at times even better than the original.
Ajay Devgan and Kajol share much better chemistry than Kevin Kline and Meg Ryan (they got married pretty soon afterwards). Devgan's thug is a lot slicker than Kline's, and his moustache is much superior. Meg Ryan played her character in a cute, whiny, bratty way, whereas Kajol is equally cute in a more wacky, goofy way. Jean Reno was pretty good as the police officer, but Om Puri is even better.
Whereas casting and character interplay are actually better in this remake, technically the American original is, of course, much superior. Some of the continuity problems and location inconsistencies are downright annoying. I also don't find the slapstick scenes (like the airplane scene) too funny, but thankfully there's only a few of them.
Overall a very enjoyable movie, especially if compared to the original.