If your internet provider blocks port 80, use port 8080. Its the samething. Though you do not have to use just port 8080 or 80.
Sorry, with 128Kb/s upload (maybe 256Kb/s at best) your cable modem will always be a joke compared to a real T1. 1.544Mb/s up 1.544Mb/s down.
For my cable provider, I get 100% upload and download bandwidth. Also even the busy times I still get 100% bandwidth. My download bandwidth is 2 Mb and my upload bandwidth is 256 Kb. Its the web or ftp servers that I'm accessing slows me down. Sometimes if the server is close to me or I'm connected a few routes. My bandwidth jumps to a few megabytes for downloads.