CD of my recent Cardiac Stent placement, net program HELP

I am a new user,and I need some help from your expertise...
I had a Cardiac Stent emplaced last week and my Cardiologist gave me a CD of the entire procedure, supposedly neat pics and videos of the interior of my heart and all the nit picking precision of placing the tiny spring like cylinder] in a narrowed artery to re-establish blood flow, problem being, I am running Windows 8 and got a message that the video was in .net...is there an available program that I can Download so that I can view this interesting, to me, video. any help will be appreciated. NOTE:I am nearly, read completely, illiterate in computer stuff , not a programmer, just an old geezer/user
Thanks for any help
Coldflamingo