Well done you!
What you can do now, just for fun, is to go into your computer network settings and see if it can "see" your new TalkTalk router, which will be pushing out a wifi signal as well as the wired one that you're using via the DLink. If you can, try connecting to it (don't tick the "connect automatically" box at this stage). If it connects you'll need the password printed on the TalkTalk router and then see how you get on. As I said in my earlier post, the new TalkTalk routers are better than the old ones, so there's a good chance it will work well. If it does you can remove the DLink from the circuit (or just power it off) and then allow your computer to automatically connect to the TalkTalk box.
Go on, give it a go!