I had registered a domain in yahoo smallbusiness for just2$ but after some days my domains removed by no reason
Totally agree. I can only talk about bad experience with them, including the charge of "renewal fees" even when my domains were not longer hosted with them. I use RegisterFly, Dynadot, DomainSite and GoDaddy in this order, from good to regular.
They are not the best. They are probably rank at the bottom of the registrar and hosting solution you should consider. probably high on the list which you should not consider. Their support is pretty crappy and slow and don't expect to hear from them for days with their cut and paste answers which is usually of no help.
I don't know anyone who uses Yahoo for domain reg. Stick with GoDaddy for simple, cheap solution. eNom for more expensive, higher quality service.