"I'd rather use commercial software than Open Source alternative" This option does not make sense as you can have commercial Open Source software.
I use any software that i like, it can be paid, free or open source. However i do think that usually only geeky people tend to use open source software (Like me) because they focus less on the GUI and more on the features/speed/less bloat and the old school, ugly GUI from most open source software scares regular users.
Although I run Windows, I use a lot of Open Source applications. Freeware makes up most of the remainder. I have very little payware. Most of the Open Source applications I use are better than their commercial counterparts. IMO, Open Source developers are more inclined to listen to the users and incorporate what they want into the product. A lot of commercial software companies don't care what users want, MS and Adobe being prime examples.
In August 2010, Microsoft interoperability general manager Jean Paoli said Microsoft "loves open source" and its anti-open-source position was a mistake. (source: wikipedia.org) I use free, paid, & open source...any software that I like and works well on my OS.