There are many important things to consider when you are looking for a good webhost, but the most important thing to keep in mind is that they tell you the amount of bandwidth, storage space and email accounts you can have with your hosting purchase. This is going to allow you to know what kind of capacity you will be getting for your website.
There are other complex things that you might want to know if you are planning to do ecommerce or any complex site configurations, but for most regular websites, the best way to go is to simply make sure that you know how much your hosting offers in storage and bandwidth.