|I dont have gsview, so I cant try it out.|
I guess you can search for gswin32.exe and
on console(cmd.exe prompt) go to that directory and type "gswin32 /?" or "gswin32 -h"
and figure out how to use command line conversion tool to convert ps to pdf.
Then you should be able to insert appropriate command for conversion into your existing batch file.
You should be using something like
gswin32.exe -dSAFER -dCompatibilityLevel=1.2 -q -dNOPAUSE -dBATCH -sDEVICE=pdfwrite "-sOutputFile=YourOutfile.pdf -c .setpdfwrite -f "YourInputFile.ps"
You can not interact with a graphical windows application from batch file.
In this case, I guess gsview uses a command line program to convert internally, so you could use just that.