wifi fighting with bluetooth - please help!

Hi people,

I have the following problem:

I recently bought a bluetooth mouse and keyboard, only to realize they use the same 2,4 Ghz frequency that my router was set to, causing hiccups in both connection.

So I set the router to 5 Ghz (it's some basic modem-router the network provider gave me which can do only one band at a time) which solved the above problem but made another: flatmate's phone and notebook cannot detect the 5 Ghz network.

My questions:

- Do I have to buy a simultaneous dual band (or how you call it) router in order to have internet on both frequencies or I can get the same result going the cheaper way i.e. buying a 2,4 Ghz router and running the two routers parallel?

- If we will have internet on both frequencies, will my initial problem come up again? Will the 2,4 Ghz internet disturb my bluetooth connection even though my computer is feeding on the 5 Ghz internet? (Flatmate and I have our workstations in separate rooms, not sure if it matters.)

- Or am I thinking wrong and there is some other solution to my problem?

Any advice is very much appreciated.

(Oh, and sorry for my English, non-native speaker here.. Hope it's comprehendible.)

Daniel