Winmodem will probably give you trouble. Those aren't real modems but are software emulated and need special programs only aviable for Windows to use.
Some limited support for Winmodems are aviable (call them Linmodems then).
Everything else should be fine. I thinking that your using intel chipset, right?
On onboard sound cards they generally don't support hardware mixing, since they are so cheap. So you may have issues with running multiple sound programs, kde has a sound deamon "artsd" that is used to provide software mixing for artsd-aware programs. But the artsd daemon (think background proccess or server proccess) will grab your sound card. This is something to watch out for if your having media programs causing issues. (to fix, get a better card, soundblaster 5.1 or audigies are well supported and cheap, or enable software mixing for your alsa drivers thru the dmix plugin. Check out alsa-project.org for details)
But other then that everything should work out fine. Everything should work out of the box, except maybe with the winmodem, but that may work right away, too. But I am not sure about model specifics and stuff.