Vista won't let me listen to music download clips?

Trying to preview music clips on Puretracks.com (music download site).  First two songs downloaded smoothly & I could hear them but after that I couldn't hear anything even tho the website said "Song is Now Playing".  Another Vista user told me he had nothing but problems on this site as well.   

Why does Vista seem not compatible with many websites?  I cannot shop online at one of my favorite places now because their checkout cart does not support Vista.

Had my Vista computer for 6 mos. now & everything I seem to want to do is a problem! (sigh).  Must admit I'm a little computer-challenged but I really hate my Vista computer.   Any suggestions on how be able to listen to music clips again on my Puretracks.com website?