To be honest linux is completely unnecessary. If you want to record music but don't want to pay 600 dollars for protools, 900 dollars for what ever, and ect. Installing something like ubuntu studio would likely be quicker over all but there not an application that I'm aware of that doesn't have a windows version.
Here's a list of some free opensource apps that have some windows versions.
http://en.wikipedia.org/wiki/Ubuntu_Studio#Audio You can find these here
As far as a DAW you will probably have to use audacity. Adour and rosegarden don't seem to have a windows version unless you want to compile one yourself. Which I wouldn't want to do. audacity along with Macaw http://www.breakoutbox.de/midi/midi.html should cover you here.
@Mahesh have you tried using audacity for mastering? I know it at least has noise removal filters.