If I get another router, would I be able to use the second one as a switch and a wireless access point or would I still need to put a switch before the main router?
Yes you can do this, I myself am currently making use of old routers this way
You need to assign the old router a static IP address (I use 192.168.1.200, 201, 202, 203+ for mine) then use a powerline adapter to pipe through the data to it.
I have main router in following;
Dining Room - Huewei HG 635 (FTTC Router Dual Band Wireless N + Wireless AC)
Front Room (Wireless switched off so acts as switch - Wireless G) - D-Link 2610R
Main Bedroom D-Link DSL 2680 (Wireless N + 1 spare Ethernet port after Powerline Adapter) for upstairs wireless signal boost
Outside in Shed - Heiwei HG533 (Wireless N + 4 Port Switch - input into WAN / Fibre port - Used for Home Server and PC repairs)
They all run the same wireless name (SSID) but use different channels so as not to clash with each other and also so don't have to reconnect to a different SSID each time it hops between them as the devices as the devices will lock onto the strongest signal, and it happens almost seemlessly.
The powerline adapters I use are
http://www.pcworld.co.uk/gbuk/netwo...werline-adapter-starter-kit-16842033-pdt.html I have brought 2 packs of them and haven't regretted it since as they are all paired together although mine are 200Mbps units where as these are the upgraded versions of them but have the same product number so poss a firmware upgrade for them
Hope this helps, and if you need any help or more info, please let me know.