PAF 2.0 converting to PAF 4.0 could cause some problems using GEDCOM.The GEDCOM syntax for event dates and LDS ordinances changed with PAF 2.1.PAF 4.0 does not fully support PAF 2.0 GEDCOM.
A better way would be to convert the PAF 2.0 database to PAF 4.0. This was copy from PAF FAQ:
Q: I have PAF 2.31. How do I convert the files to PAF 4.0?
A: These instructions also work for PAF 2.0, 2.1, 2.2, and 2.3. To convert PAF 2.31 files to PAF 4.0:
Run PAF 4.0. Click on the File menu. Choose Open. Choose the (PAF data) folder you want to convert to PAF 4.0. Within the folder find the INDIV2.DAT file. Open the file (either double click on the file name or click on File and then Open). A screen will appear that will let you set some options. Set the options you want and click Continue. Type in a file name and click Save. The program will convert the PAF 2.31 file to a 4.0 file and will open the file onto the screen. Note: PAF 4.0 and PAF 3.0 cannot convert PAF 2.31 backup files. If you have a backup file, you must restore it into PAF 2.31 before you can convert the file for use in PAF 4.0.