There has been a lot of discussion on this forum about winmodems. Some will work, others will not. If you want to know if your winmodem will work, go to
and do a search on "compatibility list". You should find something there that will help you to decide if your winmodem will work with linux.
As mentioned in previous post, an external modem atached to your serial port will work with the least amount of hastle.
However, a compatible internal modem will also work fine. I use a U.S. Robotics 56K Fax PCI modem. It was easy to set up, once I learned how.
Although I have no experience with this, I believe that any hayes compatible modem should work.
In the final analysis, I think I would stick with a modem that I know is compatible.