Could you attach the .blend file? That would allow us to look at your lighting set up and configuration and figure out what could be causing the flickering. Make sure to pack the textures so we don’t end up with blank walls (File -> External Data -> Pack into .blend file).
The camera jerking looks to be a framerate issue. It appears to have been rendered at six frames per second, with every fifth frame showing for two frames.
As for the camera, the easiest way to control its rotation while following a path is to give it a Track To constraint and have it follow something, usually an Empty so you don’t have some huge object obstructing the view. The camera follows the path, and you add location keyframes to the Empty to tell the camera where to look.
To do this, create your path, then select the camera and give it a Follow Path constraint, using the name of the path you created. If the camera isn’t following the path properly, use Alt-G to clear its location. In the curve’s object data, you can use the Path Animation properties to set the number of frames for the animation, and you can set the Evaluation Time to adjust the camera’s location along the path at any given frame. (For example, if you have a 250 frame animation and you want the camera to be at the middle of the path at frame 200 instead of 125, you would set three Path Animation key frames - 0 at frame 0, 125 at frame 200, and 250 at frame 250.) From there you can use the graph editor to refine the timing.
To add the Track To constraint, the easiest way is to select your camera, then select the object you want to follow, press Ctrl-T, and select Track To Constraint. To add it manually in the Constraints properties window, add the Track To constraint, enter the object you want to follow, change the To: field to -Z, and the Up: field to Y. (Using Ctrl-T makes these changes automatically.) To understand what these mean, you can go to the camera’s Object properties and enable Axis under the Display panel. This will show the camera’s X, Y, and Z axes.
If you want to be able to rotate the camera instead of keeping it oriented to the global axes, check the Target Z button in the Track To constraint’s properties. This makes it so that if you rotate the object you are tracking, it will cause the camera to rotate as well.
(These instructions were written using the latest 2.5 build, and may be different if you are using an older build. If something doesn’t work as explained, and you can’t figure it out, let us know.)
I hope this helps! You’re already off to a great start.