HOW TO RIP TILE FROM GBA GAME

That is in fact pretty much what you do. It's a tedious, time consuming process. Fortunately, it's been done for you for a lot of games. http://www.spriters-resource.com/

author=KingArthur
4. ????
5. PROFIT!

that's a joke that just never gets old, huh?

*more to the topic, there are emulators. not sure if any of them allow shutting off layers, which lets you only see certain things. and there are programs that allow you to press a button to take and save a screenshot, if the emulator doesn't already have that function. zsnes does. you can just slow the speed of the emulator down, if possible, and press a button to take screenshots during an animation. then you just have have to sift through the many images to find all frames of what you want.

doing it with prntscrn and paint is making it harder than it needs to be. but like LockeZ said, check that site as lots of graphics are there. sometimes it won't have what you need though.

Your first problem is because of the bitmap's dimensions. Everything you import into 2k3 has to be exactly the same size as the rest of that particular content. For example, all charsets are 288x256.
Your second problem (256 colors) is because of palette issues. 2k3 doesn't support 24-bit graphics like later makers do. All imported images are limited to 256 colors.

The easiest solution is to simply export something to use as a template, open it in MS Paint or whatever, and start dropping your properly formatted stuff onto it. The palette gets mangled a little since it's trying to conform, but we all start somewhere.
More experienced users can fiddle with programs like Gimp to get things looking exactly like they should, but that's a little further down the road.