From ZDoom Wiki
The miscellaneous options menu contains all important settings that do not really fit anywhere else yet would not justify having a menu all of their own. Its MENUDEF name is MiscOptions.
- Merge left+right Alt/Ctrl/Shift (On/Off) (Win32 only)
- If set to "on", ZDoom will make no distinction between the left and the right versions of the "alt", "ctrl" and "shift" keys.
- Alt-Enter toggles fullscreen (On/Off) (Win32 only)
- If set to "on", hitting the Alt+Enter key combination toggles between fullscreen and windowed mode, following the Windows convention.
- Show IWAD selection dialog (On/Off)
- Display the IWAD selection box on startup. Note that it will be skipped anyway if a mod is loaded with a GAMEINFO lump specifying an IWAD.
- Enable cheats from all games (On/Off)
- If this option is on, then cheat codes from any of the supported games work in all other games as well. In case of conflict, such as the IDDQD "trap" in Heretic, the normal cheat code is the one that takes effect.
- Enable autosaves (Off/On)
- This option lets you turn off the autosaves created upon entering a level. Be warned that with this option turned off you will not be able to resume the game in a hub after you die.
- Save/Load confirmation (On/Off)
- Controls whether a confirmation dialog is displayed or not when performing quicksave and quickload.
- Number of autosaves (1—20)
- Allows to choose the number of autosave files used by ZDoom. If the chosen value is more than one, there is a rotation to prevent overwriting the most recent autosaves.
- Cache nodes (On/Off)
- Time threshold for node caching (0.0—2.0, by 0.1 increments)
- Determines the minimum length, in seconds, that GL nodes generation must take to trigger node caching.
- Clear node cache