actually i have already tried about 3 or 4 times, i cannot realize why these problems only happen on my computer...
i have windows xp, i don't think there are other factors that could interfere...i will try to uninstall and reinstall all the pack another time anyway...
I didn't install any mod, just bg1+tosc patched with the 5512 patch and Soa+tob with the 16498 european patch
I also added to the installation 2 translation: the first for tosc and the second for tob, but i don't think these influence on this problem, i have already done the same process for a friend and the game worked perfectly...