PrimoPDF is a freeware which converts almost any files to a PDF. The user just clicks on "print" command in the source program which was used to open the source file and selects "PrimoPdf" virtual printer. The output will be a PDF file. The software supports also the alternative to "drag and drop" source files onto a desktop icon for direct conversion.
Another useful feature of PrimoPDF is "Append or Overwrite" an already existing PDF. Document properties (security and so on) can be edited and the quality of the output PDF file can also be selected.
PrimoPDF is a fast and free PDF maker, if you are looking for a similar free PDF maker doPDF would be a good alternative.