If you've got a car, it may be cheaper to go to France or Austria.
But if you don't, I would firstly recommend Grindelwald* as it is a resort that you and the kids will never forget. It's looks like a chocolate box and is very child / family friendly.
But if you're still not sure where to go skiing, following this and other advice, go to the main train station in Basel and ask at the Tourism section. They will tell you the best deals / resorts. Get a few prices / quotes.
Once they recommend one or two places, go home and call the Tourist Information of the two resorts (and Grindelwald), and ask them for best prices (either in the town centre or near the ski school - they will know which chalets are best located).
If going by train ask for
Snow n Rail tickets at the travel desk at the station where you also get discounted ski lift pass and ski equipment hire.
So for good value, in summary I would ask the tourist information at the resort you select for the accomodation (at the price you want - not sure if they do self catering chalets) but the railway station for the best train, ski pass, ski hire deals.
Hope this helps (if you've got a car let us know so we can provide more info).
HB (Zurich)
* wow when looking for snow n rail I saw this interesting item, looks fun, anyone tried it:
http://ext.sbb.ch/TravelTips/Bernese...t-Flieger.aspx