Picked this up since it was on sale for 800 points ($10 versus the normal $15).
The achievement I got was for finishing the first level of R-Type in classic mode. I have to admit it was hard. Took me a couple tries. I am always amazed I had the patience to play these games back in the day. If you die in classic you restart farther back without any of your powerups which makes things a lot tougher. So I just restarted and did the first level on one life. I have to say though it was really rewarding when I did finish it.
I will rally this on the new mode where you get unlimited lives for the rest of the game.