Need dial-up friendly install on USB stick

[Richard Owlett <rowlett@pcnetinc.com>]

I'm currently a Windows user who's trying to escape.

I have an unusual batch of constraints:
1. It must reside *completely* on a USB stick and be able to
   read/write an existing NTFS hard drive.
2. It must be able to connect thru a USB modem, USROBOTICS USR5637.
   a. It will be used on a desktop ( *NO* high speed internet
      ever _available_ ) and on a laptop (WIFI equipped) which
      will often need dial-up.

I've experimented with "live editions" to determine hardware 
functionality. As a permanent solution - DOA!

Using YUMI-0.0.2.5 I've tried:
  debian-live-6.0.1-i386-lxde-desktop.iso
  ubuntu-10.10-desktop-i386.iso
  lupu-525.iso
  multicore_3.7.1.iso
Using Unetbootin I tried:
  linuxmint-11-gnome-cd-nocodecs-32bit.iso

All but Multicore had lsusb available and recognized the USB modem.
Only Puppy had a dialer - it could connect but repeatedly dropped 
carrier for unknown cause.
Mint and Multicore recognized the laptop had WIFI capability - a 
protected WIFI system is nearby.

I've roamed the web for a couple of months (no longer sure Google is 
really a friend ;) I was originally referred to Ubuntu but I've come 
to think is fundamentally I need Debian style repository , much else 
is negotiable.