Keep GUI active while performing background tasks

Hi,

I'm using 2009b on a isolated network so I can't easily post code.

I have a GUI that reads in files and performs tasks on the those files such as listing available data, displaying data, etc. Reading in the file is done via a .Net function call and can take 20+ seconds. While the file is being read in, I'd like the GUI to be fully functional. Right now, when the file is being read, the GUI is not responsive and it is very clunky if I try to move it.

Is there any way around this problem?

Thank you in advance!

Scott