IE is broken period

All browsers are broken in one way or the other, if you want 100% standard compliance.

As for IE, Except for some small Javascript+DOM issues, IE8 and higher works. And you do not need to support older versions. The oldest Windows versions still supported by Microsoft are XP and Windows Server 2003, both of which can (and should, from a security standpoint) run IE8.

Where you run into trouble with various browsers is fancy CSS positioning and transitioning stuff, table'd layouts on the other hand work just fine and adapt very good to the browser window size.

So, yes, IE has a lot of bugs. But guess what, Firefox has it's own share of rendering bugs and sometimes needs a few plugins to keep it happy. Chrome&Chromium have their own share of problems. Most touch-screen optimized browsers have broken Drag&Drop API's or require special Javascript treatment. And there are the text-only browsers, often used in conjunction with screenreaders or Braille terminals, that may or may not support CSS at all.

So, name me one browser that isn't broken.