Dear patio and Rustys,
I've got repeat rate set at max like I had it in Windows XP before. I didn't see Access Centre in detail but any key on the keyboard I press and hold like that, happens to malfunction. I've also observed I can't write instantly after clicking the box, for example a Facebook chat. System seems to eat up few first letters, then I can see the rest of text there. Always the same quiet and short sound is played by Windows after that happens. Rest of my PC doesn't look laggy, only the keyboard has problems.
Yours sincerely,
SlawekPL