@sallu4u, hi !
Above all I'm very grateful to you for your kind advises.
As your suggestions I re-installed Adobe Flash Player (v10.1.102.64) and I restored the default settings in my IE (v8.0.6001.18702).
FYI, the first time indeed I had to hit once the TAB key and the screen properly self-resized. Later on, no further glitch did occur, i.e. the screen - with the correct meter - readjusted (by) itself after the advertisement.
Therefore I wish to thank you for your assistance in troubleshooting.
Have a nice day and ... have fun. :-)
Cheers,
RobertoSCH, from Switzerland