Hi too Dillon14,
I'have the same problem and same OS, same Duemilanove, same Arduino IDE version, but maybe just different on CPU.
i've solved this problem just now
try this :
0. Download CDM20814_WHQL_Certified.zip from this page http://www.ftdichip.com/Drivers/VCP.htm
, if fail try from http://www.ftdichip.com/Drivers/D2XX.htm
choose drivers for windows, mine's version 2.08.14, then extract it anywhere you like
1. Plug your duemilanove to USB port,
2. go to Win 7's Control Panel->System->Device Manager, see if there's USB to Serial/ on the "other devices" menu or "COM &LPT Ports"
3. Right Click and choose Update Driver
4. Click on "Browse my computer...."
5. and put your CDM20814_WHQL_Certified.zip extracted folder, as the folder of your driver location, click next and after that...
6. I hope you'll see USB Serial port (COMXXX) XXX here's is where your Duemolanove's USB port
7. Try Open Arduino 022 IDE pick your samples compile it and upload it ....
8. Test it...
the lesson here's maybe the things don't work out very well between your Win 7 and FTDI USB driver and our beloved Duemilanove boards
, so we must reinstall FTDI USB Serial Driver on Win 7
Hope it helps
warm greeting from Indonesia