December 2016:- I think the most used Windows programs for soundcard SDRs are:-
Receive and Transmit:-
PSDR Most comprehensive (and more complex to setup). All modes, good for CW.
HDSDR All modes but CW TX is not fully implemented.
ROCKY SSB/CW/PSK Reckoned by many to be best for CW.
QUISK Not used too much but a good program. Good for CW.
LINRAD Not a traditional Windows interface but possibly worth the effort learning.
Receive only:-
SDR-Radio A program in progress v3 is said to have some form of TX soon.
All the above links go to places in my more comprehensive list where there is more information and links to the download pages. https://sites.google.com/site/g4zfqradio/soundcard_sdr_software
Read everything on the software pages, check all links for help and information. If there are associated groups join them and check the files section and other information links in that group.