Look at the wkhtmltopdf
] project, which is “simple shell utility to convert html to pdf
using the webkit rendering engine, and qt.” I'm using this in my project about two years and it works just fine.
wkhtmltopdf www.myhomepage.com myhomepage.pdf
for local file:
wkhtmltopdf c:\path\to\file.html file.pdf
.html extension is mandatory, in case you want to work with temporary file!
For executing another programs from your code use Process Class
] with ProcessStartInfo Class