I only use strategy guides for RPGs because I'm a perfectionist. And some levels like the Water Temple in Zelda are just damn impossible to get through without some form of help.
I don't use codes unless it's to unlock a costume or something superfluous. Except for the Matrix. Codes were mandatory for that game to be remotely fun.
Yeah, the Water Temple was ridiculous.
I for one, use cheats when I'm stuck at a level. I get very busy and my attention span is very limited when it comes to games. Either I beat the game in the two days off I get, or I try to beat it the next couple of days after that. But, once I start playing another game, I never will finish it, so I use a cheat to get past the really tough parts.
I also use cheats when the game is cheap. For example, facing an boss, who is crazy ass tough, but when you wittle his health down, he gets it back, and then the cycle repeats itself. Thats when I use a cheat, because the learning curver is so unbalanced, its almost impossible, unless you keep on playing for months to beat it. But I, dont have that type of time to actually do that.