There are many ADSL Broadand Internet providers and they all offer various packages, which make choice confusing, though in the Worthing Area Virgin Media offer Cable Internet, whilst the rest of the area I work in rely on BT Phone Lines.
Most providers offer a telephone call package, though Sky, TalkTalk, Orange and BTYahoo are configured to work with their supplied hardware, Orange and BTYahoo's Free Phone Calls must be routed via VoIP http://en.wikipedia.org/wiki/Voip and this is not over a standard BT Phone Line.
Currently Tiscali and Pipex currently offer Broadband with Phone Call Packages which does not rely on using their supplied equipment.
Please note AOL may require different hardware requirements, whilst Virgin Media recommend to purchase their Netgear Wireless Router from them due to the authenticity procedure they use.
An alternative to either Cable or Phone Line Internet is 3G Broadband which is available from the Mobile Phone Providers, as it uses the Mobile Phone Network, the biggest issue is receiving a decent signal. I average in the region of 2meg Speed with both Vodafone and 3 Mobile, which is considerably slower than most Home Broadband.
All providers supply a USB Mobile Internet Adaptor which limits the use to one PC/Laptop, though a Router which is compatable with most USB MIA's is available from http://www.solwise.co.uk/3g-routers.htm for around £60.00 which allows shared internet connections and so much more.
Many households and small businesses wish to share Broadbandand Connections between Computer and/or Laptops even Games Consoles. Whilst the current trend is to utilise Wireless (WiFi) Networking, the main limitations are loss of signal and interference with other electrical equipment.
If poor Wireless Signal is experienced then there is an alternative in Powerline Networking which uses the Mains Electrical Circuit to carry the signal, the main benefits are enhanced security of your network and the simplicity of setup, not to mention flexibility. Home Plugs are around £25.00 each http://www.ebuyer.com/product/150039 and will work with most presently installed equipment, ie PC's, Laptop's and Games Consoles.