On the what you will be eligible that will depend on how much TalkTalk value your custom, different people get different deals, it is normal in a home move to move people based on their current contract.
Of course nothing stopping you ceasing the service when you move out, and applying under a new name and bank account at the next address.
For basic TV, BT TV and Infinity 1 which is £10 per month for 12 months, or there are more channels in the Entertainment Plus for £17.50 per month (http://www.thinkbroadband.com/isp/bt/package/1351.html)
A lot hinges on what you want from the TV side, e.g. TalkTalk can offer some Sky channels. or you can get your own FreeView PVR and then add a Chromecast or NOW TV box for on demand stuff.