These days you should go for at least 2MB. 1MB is still ok, but it's nicer when you have a lot less disk swapping

Of course all laptops have video cards. Here you might want to do some research. Some video cards will mention the word "shared" or something like that, and that means that they are using the regular RAM as video memory; this is usually not a very good idea. So a proper video card is the way to go. Still, many laptops have decent video cards.

For anything other than the most specific applications, the average sound card is ok, so i would't worry about that.

And I wouldn't worry too much about the processor, although you might want to compare a little to avoid being at the bottom end.

In the end, a big factor in the laptop purchase is the kind of use you want to give to it. You may enjoy a big screen, but that makes the laptop bigger and eventually heavier. If you will be using it on batteries a lot, battery life becomes an issue, while otherwise you wouldn't even think about it. And depending where and how you transport it, size and weight could be important too.