I am using kazaa lite for about 5 months and I dont face a problem out of that. Kazaa lite is kazaa 2.0 version with no spyware included. If you are using that it will prompt for upgrading and never do that. If you upgrade you will get the free spyware.
There is another program called kazaa speedup. I think this also contains a adware. When I installed I found some adwareZ got installed in my system.
If you have problems with spywareZ and adwareZ then use ad-aware. Ad-aware is a free, powerful addware remover which searches for the adwareZ installed in your system. You can then remove it, but his may affect some of your installed programs like NetAnts. NetAnts require a adware to be installed for running. Its name is Radiate. Actually it is harmless and included to provide NetAnts free. Either select not to remove Radiate component or reinstall Netants to keep it working again.
Kazaa is the most popular peer to peer sharing utility. It help us to search for the shared files and user can download the files easily. It is having its own player for playing the multimedia files. Some times it may take days to get a big file get downloaded. But if you want to get a game or movie or some good software for free of cost, then what is the problem in waiting for a week or two.
Another problem is that, the wareZ you are downloadig may containing virus. so please keep your Norton on while downloading via Kazaa.
I like this software very much. I use this for downloding some utilitis, multimedia files and gamez ;-).
Thanks to its providers for giving such a wonderful software.