Well, if we are going to consider the so-called RAIL-SHOOTERS, I'd go with the excellency of

Panzer Dragoon I, II & Orta(Saturn, Xbox)

Star Fox (SNES, N64)

Tempest 2000 (Jaguar, Saturn)

REZ (Dreamcast, PS2, Live Arcade)

My top-ten(with no particular order)

Radiant Silvergun (SAT)
Layer Section 2 (SAT, PS1, PSN)
Blazing Lazers (TG-16)
R-Type series (Arcade, multiple platforms)
Ikaruga (Dreamcast, Gamecube)
Truxton (Arcade, Genesis/Mega Drive)
Thunder Force series (Arcade, Genesis/Mega Drive, SAT)
Under Defeat (Dreamcast, PS3)
Lords of Thunder (Turbo-Duo)
Space Invaders (Arcade, multiple platforms)

Special mention to Gate of Thunder, that could be in Lords of Thunder place. People will often argue about which is better. I put Lords of Thunder on the list because of its fantasy atmosphere.

FIGHTING VIPERS is a great game. The destructible armor-esque was innovative at that time. But, in terms of mechanics and gameplay,

LAST BRONX is definetily better.

Can you imagine a Virtua Fighter with weapons? It's called Last Bronx. It has deeper gameplay than Soul Edge.

Also worth mentioning is

ANARCHY IN THE NIPPON

(It has amazing graphics. And also the art direction has some key elements that will appear in Shenmue. Notice, for example, that the blond girl's stage - I don't know her name, the menus are in japanese - appears to be exactly the same harbor that Ryo Hakuzi finds his part time job in Shenmue 1)

- Oh, and just on a side note: did you guys already know that AM2 classics are coming to XBLA / PSN? Sonic the Fighters, Fighters Megamix and Virtua Fighter 2. Although I still play FV and VF2 on my Saturn and STF on emulators, I'll buy them to get some achievements!

For the one who said "it doesn't have any standout game", this is simply ridiculous. Virtua Fighter and Daytona USA alone represent a huge importance for fighting and racing genre, respectively, that one cannot deny it.

Without Virtua Fighter, there'd be no Tekken, Soul Edge, Soul Calibur, Dead or Alive... Virtua Fighter is as paradigmatic for 3D Fighting genre as Street Fighter wa s for 2D fighting. Virtua Fighter 2 is considered the chess of fighting games, being revered 'till nowadays.

Without Daytona USA, there'd be no other classic arcade racers such as Ridge Racer, Super GT, Sega Rally(Super GT and Sega Rally being also from SEGA). Daytona is as paradigmatic for arcade racers as Gran Turismo was for simulation racers. And Sega Rally is also available on Saturn. It has perfect playability(just as Daytona also has).

Radiant Silvergun is considered the best shmup of all time, period.

Nights introduced the analog controller. For my taste it may be childish, but it also has smooth playability. And is available on Live Arcade and PSN.

... and what about Panzer Dragoon? Perfect playability, and fantastic art direction. Without Panzer Dragoon, there would be no REZ or Child of Eden.

You're right, these game doesn't age well... because they simply DO NOT AGE. That's why they're CLASSICS.

And classics remain enjoyable forever.

Oh, you mentioned DECATHLETE. Don't forget WINTER HEAT, which is also excelent.

I'll mention two that are absolutely essential

SEGA RALLY CHAMPIONSHIP & DAYTONA CCE

?

Both are such great games, even nowadays. Both mechanics and gameplay remain as enjoyable as within the moment they were released back then. Simple to pick up, but difficult to master - in a way that will trully hook you up. Its mechanics and playability still impresses me nowadays, and I keep playing them both.

Other two that are not classics, but both enjoyable games:

HIGH VELOCITY MOUNTAIN CHALLENGE

TOKIO HIGHWAY / SHUTOKOU BATTLE

I would add two fighting games that, although not critically well-received as Virtua Fighter, still are great, at least for me.

LAST BRONX

(can you imagine a Virtua Fighter with weapons? It's called Last Bronx. It has deeper gameplay than Soul Edge.)

ANARCHY IN THE NIPPON

(It has amazing graphics. And also the art direction has some key elements that will appear in Shenmue. Notice, for example, that the blond girl's stage - I don't know her name, the menus are in japanese - appears to be exactly the same harbor that Ryo Hakuzi finds his part time job in Shenmue 1)

And, concerning shmups, I'd add

LAYER SECTION II

(Also, amazing graphics and effects. Solid gameplay. Nice challenge. There's a remake on PSN. But I prefer to play it on my Saturn)

THUNDER FORCE V

(same reasons from the one mentioned before)

Last, but not least, in the action genre I'd add

PSYCHIC KILLER TAROMARU

(An underrated gem. Great art direction.)

Did anyone mention

SEGA RALLY CHAMPIONSHIP

?

I don't think so. It's such a great game, even nowadays. I mean, along with Daytona USA, its mechanics and gameplay remain as enjoyable as within the moment it was released back then. Simple to pick up, but difficult to master - in a way that will trully hook you up. Its mechanic and playability still impresses me nowadays, and I keep playing it.

Did anyone mention

SEGA RALLY CHAMPIONSHIP

?

I don't think so. It's such a great game, even nowadays. I mean, along with Daytona USA, its mechanics and gameplay remain as enjoyable as within the moment it was released back then. Simple to pick up, but difficult to master - in a way that will trully hook you up. Its mechanic and playability still impresses me nowadays, and I keep playing it.

I would add two fighting games that, although not critically well-received as Virtua Fighter, still are great, at least for me.

LAST BRONX

(can you imagine a Virtua Fighter with weapons? It's called Last Bronx. It has deeper gameplay than Soul Edge.)

ANARCHY IN THE NIPPON

(It has amazing graphics. And also the art direction has some key elements that will appear in Shenmue. Notice, for example, that the blond girl's stage - I don't know her name, the menus are in japanese - appears to be exactly the same harbor that Ryo Hakuzi finds his part time job in Shenmue 1)

And, concerning shmups, I'd add

LAYER SECTION II

(Also, amazing graphics and effects. Solid gameplay. Nice challenge. There's a remake on PSN. But I prefer to play it on my Saturn)

THUNDER FORCE V

(same reasons from the one mentioned before)

Last, but not least, in the action genre I'd add

PSYCHIC KILLER TAROMARU

(An underrated gem. Great art direction.)