how do i delete old games from save/load screen:(

Use Windows Explorer.

Assuming you're playing Vanilla Civ3, and did the default installation, go to C:\Program Files\Infogrames Interactive\Civilization 3\Saves. The saves will be in that directory.

You can also put WindowsFileBox=1 in your civilization3.ini file, and that will give you the standard windows file dialog box. You can delete from there.