Notepad in Windows 98 and Windows ME don't know the usual accelerator key shortcuts.
How to improve:
Open notepad.exe in Resource Hacker and edit Menu-1 and Accelerators-1.
Here you see my modified NotePad.exe for the German Windows ME Editor.
1 MENU
LANGUAGE LANG_GERMAN, SUBLANG_GERMAN
{
POPUP "&Datei"
{
 MENUITEM "&Neu\tStrg+N",  9
 MENUITEM "Ö&ffnen...\tStrg+O",  10
 MENUITEM "&Speichern\tStrg+S",  1
 MENUITEM "Speichern &unter...\tF12",  2
 MENUITEM SEPARATOR
 MENUITEM "Seite ein&richten...",  32
 MENUITEM "&Drucken\tStrg+P",  14
 MENUITEM SEPARATOR
 MENUITEM "B&eenden\tAlt+F4",  28
}
POPUP "&Bearbeiten"
{
 MENUITEM "&Rückgängig\tStrg+Z",  25
 MENUITEM SEPARATOR
 MENUITEM "&Ausschneiden\tStrg+X",  768,  GRAYED
 MENUITEM "&Kopieren\tStrg+C",  769,  GRAYED
 MENUITEM "&Einfügen\tStrg+V",  770,  GRAYED
 MENUITEM "&Löschen\tEntf",  771,  GRAYED
 MENUITEM SEPARATOR
 MENUITEM "Alles &markieren\tStrg+A",  7
 MENUITEM "Uhrzeit/&Datum\tF5",  12
 MENUITEM SEPARATOR
 MENUITEM "&Zeilenumbruch",  27
 MENUITEM "&Schriftart...",  37
}
POPUP "&Suchen"
{
 MENUITEM "&Suchen...\tStrg+F",  3
 MENUITEM "&Weitersuchen\tF3",  8
}
POPUP "&?"
{
 MENUITEM "&Hilfethemen",  5
 MENUITEM SEPARATOR
 MENUITEM "Inf&o",  11
}
}
1 ACCELERATORS
LANGUAGE LANG_GERMAN, SUBLANG_GERMAN
{
 VK_INSERT, 769, CONTROL, VIRTKEY
 VK_F1, 5, VIRTKEY
 VK_F3, 8, VIRTKEY
 VK_F5, 12, VIRTKEY
 VK_BACK, 25, ALT, VIRTKEY
 "^Z", 25
 "^X", 768
 "^C", 769
 "^V", 770
  "^A", 7
 "^F", 3
 "^N", 9
 "^O", 10
 "^S", 1
 "^P", 14
 VK_F12, 2, VIRTKEY
}
2 ACCELERATORS
LANGUAGE LANG_GERMAN, SUBLANG_GERMAN
{
 VK_INSERT, 769, CONTROL, VIRTKEY
 VK_F1, 5, VIRTKEY
 VK_F3, 8, VIRTKEY
 VK_F5, 12, VIRTKEY
 VK_BACK, 25, ALT, VIRTKEY
 "^Z", 25
 "^X", 768
 "^C", 769
 "^V", 770
 VK_ESCAPE, 28, VIRTKEY
 VK_C, 28, CONTROL, VIRTKEY
 VK_D, 28, CONTROL, VIRTKEY
 VK_Z, 28, CONTROL, VIRTKEY
 "^A", 7
 "^F", 3
 "^N", 9
 "^O", 10
 "^S", 1
 "^P", 14
 VK_F12, 2, VIRTKEY
}
Don't forget to compile every script change and then save the EXE File.