Many TVs now come with Smart features. In fact, it's getting harder and harder to buy a non-smart TV of any quality. The technology is filtering down so that those TVs that aren't smart are really very basic models.
As far as set-up is concerned, make sure that the house wireless router is using the same security level as the TV. If the router is using some higher grade encryption than the TV then you won't get a connection. Other than that, and making sure that a) the wireless signal reaches the TV, and b) you've entered the wireless password correctly, then that's about it.
In terms of smart TVs in general, there are a couple of key observation to be aware of. The first is that manufacturers only support a limited range of services, and some of those services either may go off completely e.g. Ch5's Demand 5 service - or that the TVs own firmware might not be updated sufficiently 3-5 years down the line to cope with updates in the various online services. IOW, have a back-up plan.
I have seen folk buy smart TVs expecting to surf the web like they do with a PC and thinking they can download apps from all over. Neither of those is not the case. If the TV does have a browser then expect it to be laggy and difficult to operate because you're text-typing 'ABC' 'DEF' 'GHI' which is painfully slow. Also expect the be shepherded through some kind of manufacturer portal that filters the search results. As for 3rd party apps, that's off the table completely. If the app doesn't come from the manufacturer's own web site as a download then it's unlikely the TV will have the necessary coding to run it.
That's the doom and gloom bit over. Now for better news.
Smart TVs with Android TV as an interface are more flexible. Sony is one of the manufacturers that have realised that the operating system for smartphones does much of what they'd like to do with their TVs far better than some clunky corporate interface.
Alternatives: Keep your existing TV and add a Smart box.
There are loads of 3rd party media player boxes and gadgets out now that can be connected to your TV's HDMI socket. Google Chrome is one of the cheapest at around £30. It is a plug in stick and is controlled by your Android Smartphone. Apple has Apple TV at around £80. This is controlled by an iPhone. Apple TVs content is all funneled through iTunes but there's a decent selection of stuff. If you're already an iPad user then you'll love screen mirroring. Basically anything you can watch on a iOS tablet or phone can be sent to and viewed on the TV. Apple call this 'Airplay'. Android and Google call this 'casting'.
If you prefer a box that doesn't require phone or tablet for control then there's still plenty of options. Apple TV works well from the supplied remote control handset. Roku, Now TV, Android MX are all small media streaming players that cost under £70 and will work with a broad range of aftermarket apps. This means they're not as restricted as the main manufacturer smart TVs or Apple TV.
At home my family watches streamed content via an Android MX box. This uses the same operating software as an Android Smartphone and provides a way to stream only content and movies and TV shows from my home's own media library. The Android box comes with a remote, but I also added a full size wireless keyboard with mousepad with makes web surfing so much easier.
