The netbook is upgraded now: Samsung 250 GB hard disk and an additional 512 MB RAM. W7’s performance index (graphics) doubled to 2.0 by adding the memory. I just got an ebay hit (4x 512MB for 1,5) so I tried that and I think it will suffice for the time being. I got a neopren cover so the netbook will survive in a backpack (hopefully).
I got a dual DVB-T USB TV receiver that is media center compatible (MSI DIGIVOX Duo). Media center runs very smooth even on such an impotent machine. The MSI drivers seem to be a bit instable because I got machine hangs several times when I switched TV on.