I've already reviewed the original eight Mega Man games on this site, so I don't feel that it is necessary to do it again. Here are some links to those reviews:

Although for the most part the originals have been kept intact, some changes have been made in the translation from the old NES to the newer consoles. For one thing, I found that the music in some of the introductory cinematics no longer syncs up with the length of the little story like it used to on the NES. That's odd. Secondly, and perhaps more importantly to many a language enthusiast, some of the most beloved spelling mistakes of the past, particularly the one in Mega Man 6 where Dr. Wily admits that his plan had "faild", have been fixed. This is most disappointing and even though it doesn't take away much from the overall gameplay experience, it takes away from the nostalgic value of the games compared to their original state. On occasion, the Robot Masters are a bit easier or a bit more difficult than you might remember from the olden days. And lastly (and more naturally expected), the control scheme has been affected. Due to the different configuration of buttons on a PlayStation 2 controller (and GameCube and Xbox controller as well), you'll need to get comfortable with new buttons doing different things. I've heard the GameCube control scheme is the most uncomfortable of the three consoles, mainly because of the strange way the "A" and "B" buttons have been reversed, but I can't officially report that. This was to be expected, so I can't give anyone grief over this. I should, however, note that I have been playing this with my PlayStation 3 and have discovered that there is a tiny bit of lag between button presses and reactions on-screen, which requires me to have even BETTER reflexes. That shouldn't be, but it's not MMAC's fault. Damn you, Sony! What have you done to my Mega Man adventures?!

In addition, we are also privileged enough to get the two Mega Man games that were only available in arcades, though they both need to be unlocked first. "Mega Man: The Power Battle" and "Mega Man 2: The Power Fighters" play like a fighting game, where you get to select a character (usually between Mega Man, Proto Man, and Bass -- plus Duo in the second game) and fight against Robot Masters from the first seven Mega Man games. The two games, though very different graphically speaking, are very much alike in their execution. You go through a series of Robot Masters before you have a showdown with a weird creation of Dr. Wily, and then go after the mad scientist himself. The best part about this is that a second player can join in to aid you in defeating the rascally Robot Masters. (Someday, I will have to come back and review these games individually.) They are a welcome addition to the collection, but frankly, they pale in comparison to the original eight games that made the Blue Bomber so famous.

This compilation would not be as complete without a whole bunch of extra features. I can only judge based on the PlayStation 2 version, the one I own, of what these features actually are. As you make your way through the eight Mega Man games, you can slowly unlock things such as art galleries (which could have used a better navigation system than NONE AT ALL), remixed music, and (for me) the very first episode of the Mega Man cartoon show. I really didn't care much about the first two, but that cartoon is really, really... bad, yes, I know. But it's fun for nostalgic purposes, and to see when Mega Man drank energy soda and when Cut Man sounded like Peter Lorre. Other versions of this compilation feature a slightly different set of included extras (for example, I believe the GameCube edition has an interview with Keiji Inafune, the creator of Mega Man, in place of the cartoon episode). Perhaps the most important extra features can be found in relation to the games themselves. Mega Man 1 through 6 had already been released in Japan in a package similar to this in the Rockman Complete Works collection for the original PlayStation years earlier, and some of the updates in that set can be found here. The Navi System, for example, was added to help players navigate through the levels better. There are also remixed soundtracks for those games, although the number of tunes that are actually remixed is much larger in Mega Man 4 through 6. Some of the in-game graphics can also be improved; like the Navi system, it must be switched on in the Options menu, or else you get the originals. I say savour the originals.