Do you use a system font or an Adobe font? You should never use a system font in order to be sure that your learners will see the font correctly. Have a look at:
http://blog.lilybiri.com/fonts-in-captivate
As for blurriness: if this is a non-responsive project, you need to know that text will be converted to images if it is not dynamic text (look at the blog). That used to be a way to allow any system font but can lead to blurriness when rescaling. To avoid that a workaround is to insert a null variable in each text container to convert it to dynamic text which will be rendered on runtime. Another workaround is to convert each text manually to SVG which is vector based but that may be lot more work. You don't need this for a responsive project where text is always rendered on runtime.
You could also opt to create the project in a much higher resolution but that will lead to bigger file sizes.