There are packages for win modem detection, and quite a few flavors support it detection that I've found. If you boot from cd, on your select flavor, there may be a recovery console of sorts, even the install console, mounting your partition. YOU CAN CAUSE DAMAGE, but it also gives a physical backdoor into your o/s to "possibly" delete, or augment system files, allowing access again. Which I don't recommend for the neophite. But whatever.
If I'm off, this is what's confusing.
"i got to reinstall linux on there sence the pc was given to me and the guy wont tell me the root password or anything"
You have a install fresh that a guy did, and he set a root password for you. Not giving it to you. Or you installed a flavor fresh, and you didn't set one? Or you set one, and forgot it? If you installed it yourself, and think there's a root password you need. If you don't set one the default is just [enter]. AS in the enter key on your keyboard.
I'd be willing to help you out if you need help, but I believe I'm a little confused by your wording up there.