If you've got a hex editor then you can patch it to default to *.* instead of *.txt

If you've got the XP version of Notepad which is 66048 bytes:

Change byte 7C0 to 2A from 74
Change byte 7C2 to 00 from 78
Change byte 7C4 to 00 from 74

The text in the combo box is wrong now but it's only a cosmetic thing

- Trevor