What is a good, common whisk(e)y that is common in almost all bars?

I turned 21 in April and enjoy drinking every so often to loosen up as I can be wound pretty tightly often. However, my band mate introduced me to Jack and Coke which is quite a good drink I find. However, someone recommended that I try just drinking scotch or bourbon straight up on the rocks. I'd like to find a good one I can get anywhere. Advice?