Hi
I had a free geocities site and a few years back registered a domain name with them and have hosted my site with them ever since. I like their hosting package because I'm familiar with it and find it reliable.
But their support is oftentimes very poor. It got so bad that I transfered my domain name registration away from them but I do keep my site hosted by them.
I'd recommend registering your domain name with a different company to the hoster, that way you have more control. If you aren't happy or have problems with Yahoo, your domain registration is seperate, should you later wish to move your site to another hosting company.