I've always heard that the pismo is the best laptop apple ever made. However, for OSX I would recommend a G4 and for programming and web development I would recommend the bigger screen. I would go with the tibook if you can find one cheap. Also, it looks like that Pismo's reserve is $1000 which sounds like a rip to me, but I've never researched a pismo, so I couldn't say. I have an iBook 600 and its great, just lacks in speed and screen size compared to my 733 Quicksilver. Also the reason D2 is loud is because it requires the CD constantly, meaning it is always spinning. This could be bad for a laptop in terms of heat, overusing the cd motor and definitely will drain the battery fast. Although with old games I have been able to make a disc image from disk copy and it works, that would save you battery and time but would take up hard drive space.
I would definitely try to find a tibook, but I think they are probably still expensive on ebay. Good Luck.