Finally, I've switched from my old Windows XP machine to a Windows 7 one running on Dell Studio Slim. I particularly like the new taskbar, explorer, control panel among others, with nice touches on them. A great improvement is seen on Windows Media Player with clean views of the library, much nicer than iTnues.
I connected my old PC and new one through the network and copied all files over, which went very well. The MWP library was successfully transferred to the new PC in this way.
The graphic driver is equipped with an HDMI output, so I can connect the PC with a high-definition TV to enjoy movies and slideshows on TV. The sound comes out from TV, much nicer than cheap PC speakers.
Windows 7 64bit
Intel Core 2 Quad Q9550 (2.83GHz, 12MB Cache)
ATI Radeon HD 4350 512MB
21.5" Full-HD screen