Hi Canturn, Spyware doctor is highly recommended by PC World (I supposed you read that issue which highly recommended this software). However, in my opinion, you are better off with the following two softwares (free):
+ Spybot Search & Destroy & Teatimer (active Spamware removal)
+ Lavasoft Ad-ware SE Personal
Reason for recommending two softwares because tests have shown that no single Spyware softwares can remove all spywares. A better effective method is of course 2 softwares!