Crossover is excellent - provided it works with the particular application you need. Personally, I use it for work - mostly to run our Avaya phone manager application + outlook.
A lot of applications still need genuine Windows, however, at which point you have to resort to either Boot Camp or virtualisation through VMWare or whatever.
However, it's generally a much better idea to try and find native applications where you can. Certainly, Toast would be a better option than trying to run Nero IMHO.