MathType is expensive, looks ugly and totally amateurish, in my opinion.
Microsoft Office: $100-200
Here is a much better and totally free system:
-OpenOffice.org: Free, open-source office package. It is way better than MS Office.
-MikTeX: A free LaTeX implementation for Windows.
-GhostScript: A free PS and PDF interpreter.
-MSYS: Open-source, minimal portable o/s interface.
-OpenOffice.org LaTeX Plugin (OooLaTeX)
Links for these free software are here:
Now you can install them in the order above and all you have to do is to show OooLaTeX where GhostScript, MikTeX and MSYS are. Then you can use it =)
The LaTeX doesn't look as crisp as the MathType equation, but that's because it's a screen shot. Normally it would look sharper than that, but that's not the point. The point is that if this is the look you want, you can almost achieve an identical look with MathType as what you get with LaTeX.
BTW, for MathType users, you create an expanding integral by holding down the Shift key when you click on the integral template in the palette. Don't use this when you're using MathType to create LaTeX though, because it will give you a translation error. Just use the normal integral, and the LaTeX renderer will expand it if necessary.