Whether disc brakes are better or not, depends on what application you plan on using them for. Road bike? Mountain bike?
For mountain bike use and possibly even a commuter bike, yes, disc brakes will be much better. They can provide more power, better control and they can _usually_ be easily modulated. They will almost always be better in rain and wet weather, which I think it one of the main advantages of using disc brakes.
On the other side of the coin, if this is your first time switching to a disc brake setup, then you will have something new to learn in terms of maintenance and brake adjustments. Of course, anything can be learned... Disc brakes will also weigh a bit more than traditional rim brakes.
Personally, I will always go with a bike with discs. Reason being, is that I know they will always work, no matter the conditions. They are reliable and provide the confidence that I need when I am riding a bike, whether on the road or on the trail.