Pros: Many improvements over the original, good soundtrack, tons of play value.
Cons: "Start/Restart" gameplay may prove too frustrating for some, graphics could technically use some beefing up.
The bottom line: While not without its flaws, Tony Hawk's Pro Skater 2 is a very good action/sports game. And recommended for the five gamers who still have never played it.
In my review of Tony Hawk's Pro Skater 1 (http://www1.epinions.com/content_171681681028), I declared it one of the most overrated games of the last generation. Looking back, I was probably a little too hard on it. It was certainly a very new type of game. And unique in the sense that it was a game you could casually play whenever you wanted without worrying about a convoluted storyline or overly steep learning curve (of course, getting good at it was a whole 'nother story). One year later, Activision and Neversoft released Tony Hawk's Pro Skater 2. This and Final Fantasy IX were basically the last major releases for Sony's aging Playstation 1 (later PS1 games, with a few notable exceptions, would either be inferior ports of PS2 games or lousy shovelware rubbish). And while THPS2 isn't without its flaws, it's a definite improvement over the original. And a fine farewell to the PS1.

Gameplay

Tony Hawk's Pro Skater 2 plays very much like the original. You skate across multiple skate parks, each one subsequently unlocked as you complete certain objectives or rack up a certain number of points in previous parks. While the park design in THPS 2 is generally similar to that of THPS 1, the sequel takes on a slightly wackier and more complex approach. For example, in the first park (Hangar), you are initially limited to about half of the park, because there's an airplane blocking your way to the other half. By grinding the airplane's propellers, you can start it up so that it flies into the second half of the park, opening it up for you. Very clever! The parks are also a bit larger in THPS2 (though not by much), and decidedly more challenging.

And when I say "challenging", I mean it! Be prepared for the same "Start/Restart/Restart" gameplay of the original THPS game. Of course, this makes the gameplay very repetitive after a while. So THPS2, as with the original, is best played in short spurts rather than one long play session.
The original game's skating contests also make a return (complete with a few funny voice-overs randomly opening some of them), and getting even a bronze in these contests will require lots of practice - even more so than the in the original's contests.

Rather than simply hunting for video tapes the way you did in the original, THPS2 has you earning money through various objectives and tricks. With this money, you can purchase new parks, upgrade your rider, etc. This is a much better system than the rather bizarre video tape system used in the original. And gives you a much more lifelike goal when playing through the game.

The most lauded gameplay innovation in THPS 2, however, is the introduction of the Manual. With a simple flick of the control stick, you can tilt your board slightly upwards and skate on a 45 degree angle (using only your back wheels). This may not sound like much, but it's one example of where big things come in small packages. You gain points for performing Manuals, and can add these points to any combo you began before performing the Manual, as well as any combo you perform right after getting off the Manual. In the original, once you hit the ground after a combo, that was it. Your combo was finished. In 2, however, when you see yourself hitting the ground, you can simply perform a Manual and then continue your combo while racking up the same number of points. This seemingly-small feature opens up endless possibilities for new tricks.

Meanwhile, the controls have been loosened up a bit from THPS 1. Which is a good thing. Grinds are considerably less awkward and easier to perform. While tricks feel a lot smoother and more natural, thanks to this rather important tweaking.

Graphics

Strangely, the graphics in THPS 2 (from a technical standpoint) actually took a slight step down from the graphics in the original. The characters are more jagged, and appear slightly less detailed. Ditto to the environments. Fortunately, what THPS2 loses in graphical finesse, it makes up for in personality. The environments in THPS2 are much more lively and interesting than the sometimes drab environments of the original. They're more colorful, have more activity, and are just all-around more "alive."

Sound

Like THPS1, as well as every future THPS game, THPS2 uses an entirely licensed soundtrack. While THPS1 was largely limited to underground punk and occasional hard rock, THPS2 features a decidedly more varied soundtrack, consisting of punk, rap, rock, and even a little reggae. And while Primus, Goldfinger, and to a lesser extent The Suicide Machines were the only real "known" bands on the first game's soundtrack, THPS2 features a much more mainstream soundtrack. Including Rage Against The Machine, Public Enemy (with metal greats Anthrax), and even the then-hot Papa Roach. Surprisingly, despite my fandom for underground music, I actually prefer THPS2's soundtrack to THPS1's. It's lighter, more varied, and just all-around more enjoyable.

Overall

Tony Hawk's Pro Skater 2 is a definite improvement over Tony Hawk's Pro Skater 1. Many of the original's issues have been ironed out for the sequel, and while some still exist (the aggravating start/restart/restart gameplay being the most obvious), enough have been fixed to make THPS2 an all around better experience. A good buy if you can find it used (it is, after all, over seven years old!), and a worthy closer to one of the greatest gaming consoles in history.