You won't be able to resize any of the modal windows in the CS, like the quest window or the AI package window. But the CS runs fine under Windows 7. You might try using the CSE. shadeMe has fixed up a lot of the windows, so maybe the quest window will behave better for you.
You can get the http://www.darkcreations.org/forums/topic/1660-construction-set-extender/ from Dark Creations. Even though it's a beta, it has a ton of bug fixes and I recommend using it. You can use it to develop mods even if they don't require OBSE.