If you need to add a generic / text only printer in XP, go to Start/Printers and Faxes/Add a printer. Set the port to PRINT, otherwise you will need to select the 'Print to file' option when printing. The Generic / text only option appears under the Manufacturer name Generic.BrainStorm will open any file but if the content is held in a proprietary (ie non-text) format, it will appear as gibberish at worst, or a mix of text and gibberish at best.
But there are two ways to import text from another program into BrainStorm.
One is to switch Magic paste on in BrainStorm. Select the format options to suit your needs. Then, in the other program, 'select all' or select the portion of text you would like to see in BrainStorm, then copy. When you return to BrainStorm, you will find all the selected text there waiting for you.
The other is to use your other program's 'save as' or 'export' capability to create a text file which you can then open with BrainStorm. (You can also print to a text file by selecting the 'Generic / text only' printer.)
Other versions of Windows will have similar functionality, although you may need to download a Generic / text only driver if it doesn't appear in the list of printers.