There's some lovely areas but a lot also depends on your budget. Is your DH working in Leeds centre? Will your DC be going to school? What's your budget?
Are you wanting a house rather than a flat/ apartment? Two/three bedrooms?
Speaking generally, without this info, Pudsey, farsley, rodley are all nice areas, more to do in Pudsey or farsley as Rodleys quite small. Horsforth and calverley also both nice but a fair bit pricier.
North Leeds is your most expensive area, chapel allerton, roundhay, moor allerton etc and unless you've got a huge budget there's some not so nice areas that are far worse than choosing an average-nice area of one of the other parts.
Otley and yeadon are both nice I've heard, but don't know enough about them.
Meanwood is up and coming, but depends on area again. Guiseley and rawdon are also nice but more on the expensive side.
Good train links from horsforth, new Pudsey, headingley/ kirkstall.
Headingley is very student orientated but kirkstall has a fair bit of new housing and a new shopping centre.
Hope that helps!