Well, tomb kings just got a whole lot better because in the olden days they collapsed when one model died, but that's no longer the case. Undead are ok for a newbie, about as challenging as any other army~ it's rough, though, because to play at your best you would have to acquire the new end times book as well as the TK and VC books. If that's fine with you, then go ahead! TK are a bit overpriced for what they do, but they have builds that work, namely lots of skeleton archers and warmachines. I don't know much about VCs, but they have some very cool units... What sort of a playstyle do you prefer?
If you go down to the woods today, be wary