Fibre Router Questions

[#1]

I had fibre installed last month and girl the most part I'm very pleased
I have a couple of questions though...
1) The new router seems to have a decreased range or at least seems to struggle to hold onto the connection as I move further away.. It looks pretty much the same as the old one so is this something to do with the fibre?  
Is there anything I can do to improve the range, prior to fibre it was fine
2). My old router had 4 ethernet cables plugged into it but as one of the four inlets on the new one is taken up by the fibre i now have only 3 I can use.  What is the best way to extend this please?
Many thanks

[#2]

1) Moving to fibre shouldn't make a difference to the wireless range.  It could be that with the new router you're on a different channel to the one you were on before and it might be more congested.  Have you tried different channels to see if that makes a difference?
2) It sounds like you have a lot of things with a wired connection, rather than wireless.  Is there any particular reason for this?  A quick and cheap solution might be to buy a switch such as the one here.  It's just plug and play and you simply plug it into one of your router's ethernet ports and it will give you an additional 4 ports to play with.  If you need even more than that there are others with additional ports.

[#3]

I haven't tried checking the channels so I'll do that, thanks
As to the wiredness.. It transfers data faster and should be more stable, no?

[#4]

It really depends on what you want it for, tbh.  For simple internet browsing and streaming etc there's no disadvantage to wireless at all.  Current speeds are quite impressive.  Gamers have a preference for wired as it tends to have better latency and games are much more susceptible to interference but for everyday use most people won't notice the difference.
If you have a decent signal then wireless should be able to cater for most needs.  Things that can affect it are channel congestion, where all your neighbours are using the same channel and this interferes with your signal; and router positioning: higher is often recommended and things like very thick walls etc may have an impact upon reception.  Without knowing your situation it might be worth experimenting with wired or wireless with your equipment and see if you notice a difference.
To give you some kind of idea I live in an old Victorian house with very thick walls that seem designed to keep wireless out.  My router is located downstairs and I used to get weaker signals upstairs (until I changed my router, but that's another story).  My son's PC upstairs is connected via Powerline adapter, since it didn't have a wireless card anyway, as is my internet TV / SKY box and Xbox.  All that uses just one ethernet port on the router and everything else (laptops, iPads and phones) is wireless and works fine.
One improvement I found out almost by accident.  I had an old laptop that used to be quite slow with surfing etc.  I just put it down to the fact that the laptop was old.  But when I upgraded my router I bought a wireless USB N adapter for the laptop, as it only had a "g" wireless card in it and I didn't want it to be the bottleneck for everything else.  Just sticking that adapter in suddenly transformed the laptop's entire performance and it feels like a new machine now, surfing just as well as my wired PC but from anywhere in the house..  The adapter cost £7.50 from Amazon.  So wireless is not necessarily worse than wired.

[#5]

You mention that you changed your router... This is one of my consideration points, the previous one seemed to maintain a good range throughout the house on three floors but this with this new one it gets weaker on the first floor and more so on the second.. Even though the router looks the same and is in the same position
One of the main bugbears is when I am streaming video it will be fine for maybe 20-25mins worth, but then stop?

[#6]

Not sure why it would stop after 20 minutes, I'm afraid.  Perhaps someone else could help with that one. 
I found the Plusnet supplied routers are fine for a small home but I had a couple and couldn't get a decent signal upstairs or more than a couple of rooms away, which was the reason I changed.  I bought a new Asus RT-N66u from Amazon and I have much more stable and stronger wireless signals throughout the house, reaching places the TG582N could only dream of.  At £105 it's not everyone's cup of tea, though.  One advantage is that it's dual band so newer equipment gets to use the less congested 5Ghz frequency (but you need to check your equipment can take advantage of this).  Now when my son streams his films everything else doesn't grind to a halt.  It also has 4 LAN ports as it has a separate WAN port for the Openreach modem.  It's also worth mentioning that if you stream a lot 5Ghz has a wider bandwidth, although the trade-off is a shorter range.
There are lots of routers out there.  I decided to spend the money because I figured it was cheaper in the long run for peace of mind and much better connectivity and this one came out overwhelmingly on top in reviews regarding wireless strength and stability, not to mention speed.  It was probably overkill for me on my ADSL Max (although I have absolutely no regrets) but if you have fibre then you might find an upgrade to be of greater benefit.

[#7]

Hi, you might find the tips on this support page helpful: http://www.plus.net/support/broadband/wireless_broadband/wireless_signal.shtml