Why do I need smaller wheels for winter tyres?

I run a Mitsubishi Colt CZ2 on 195/50 15 summer tyres. A local tyre centre has suggested fitting 14 inch wheels with a different tyre profile but cannot supply the wheels, so I have to buy those independently. I would like to ask the following

1- Why the smaller wheel?
2- If I bought them , where is the best place and what do I buy? ( I am thinking about the centre hole diameter and the measurement between wheel nut centres )
3- What would be the appropriate size of tyre to put on them?
4- Which make of tyre would be best?

Asked on 7 December 2012 by hurmordu

Answered by Honest John
Probably 175/65 R14s. Get the wheels and tyres pre-fitted from www.mytyres.co.uk Full winter tyre guide here: www.honestjohn.co.uk/winter-tyres/
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