What you see is the opening title screen along with a quick look at the loading/class selection menus. From there the video jumps right into NEStalgia's opening cut scene, along with the player navigating his way through the small beginning cave.
The video ends with a short battle. NEStalgia features a 3-person party battle system along with tons of monsters that use different tactics... but what you see here is the opening one-on-one "tutorial fight" with a vanilla opponent.
Due to Youtube compression framerate differences the image is a little jumpy, and effects like the screen flashes are off. In the game all effects are smooth. If you'd like to view the video in higher quality, I've also uploaded a quicktime version (10 mb)