Cordless phones are the way forward, no wires and you can move them whenever you like
The modem, being as you've got the option to go wireless, do that and see if your connection is ok, being as it's not far from the hub i'd imagine it will be.
As for the cable already connected to the modem, i would suggest you coil it up and leave it as is. If there is some furniture you can pop the coil behind, problem solved
The other alternative for your internal cable to the modem is, take a trip to ebay and get yourself a shorter premade length with connectors and just swap this over with whats already in place. If you aren't up for that then just coil up the existing cable to be on the safe side.
VM will remove or re-route the cable on the outside of the property if you want them to, but there will be a callout charge for this.
Your cheapest option would be get a wireless n dongle for your pc and coil up the modem cable upstrais, total cost £20 or so