Day after day I was looking on the same apperance screen when my FlexBuilder is starting. I thought changing the screen will be very hard to do but I tried :) And now my screen is changed yey :)
So how to do that ?
Well it's very simple - that's the same directory both on mac and windows but different path.
All you need to do is:
1. Find your eclipse plugins directory on vista that can be ex. "C:\Program Files\Adobe\Flex Builder 3\plugins"
2. Find the folder named com.adobe.flexbuilder.standalone_3.0.214193.
the numbers might be different - I think it depends on version of your flex builder.
3. The directory contains some bmp files with flexbuilder screen. Just change it with the custom bmp and that's it.
You changed your screen :)