That said, I practice my guitar exclusively on Win7. I play to CDs, MP3, and Youtube videos. I use an E-MU interface to get my mic'ed guitar cabinet sound into my Win7 box. It works great. I been using the same setup since Win2K. I use the Media Player (not Media Center) for this task. I also use Media Player to create my MP3 playlists and such, for my Android phone.
Win7 sucks, especially the Win7 Media Center, where the audio and video will never stay in sync. Sucks! Sucks! Sucks!
But it works fine for playing guitar along with my favorite songs and videos.
Also check-out Reaper for DAW recording. It is a great little program. It is free to try and only $40 for a home license. It Rocks!!!!