Install the game in C drive. It is by default the correct place for installation. By the way did you try Glory Of Fellowland? I am playing this game, and it is amazing. Give it a try at http://www.gloryoffellowland.com/
I just downloaded an old version of Day of Defeat (the original, not Day of Defeat: Source), were should I install it? I have Half-Life 1 non-Steam (WON), version 1.1.0.8. Does anybody know where I should install it (the default directory is probably not right, so I didn't even try it). Here is a screenshot of the installer, with the default directory currently set:
http://209.85.62.24/419/129/0/p232709/dod.jpg

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