I have a brand new (almost... september 08) Aluminum iMac which I bought new, not refurbished. 250 GB hard drive, upgraded to 4gb ram (dual channeled). Leopard is still pretty laggy and is not as snappy as I'd like it to be. It's 2.4ghz dual core. I wiped my friend's PC which has a pentium4 processor (single core) 3.06ghz and 1GB ddr ram, completely. I totally reformatted the hard drive and reinstalled a fresh, clean version of XP pro with sp3. Boots up in 7 seconds (unbelievable) and is VERY fast. Now, my iMac that I paid more than $1,000 for and should be much better compared to that 6 year old PC. But it boots up in more than a minute, and it gets even slower when I sign on. I don't have that many things running at once and have plenty of free memory available, and I have about 15 gb of free space but when I do maintenance to clear it to about 80gb of free space it still doesn't make any difference. It shows how a fully updated brand new copy of XP is faster than Mac. Maybe it's less stable, but it's certainly faster from what I found. I want to do what I did to my friends PC, erase my HD and reformat it compeltely and then reinstall a brand new copy of Leopard on it. So I have a few questions: 1. Which is better to use, the 2 install discs that came with my iMac, or a retail Leopard disc? Cause I have both, just wondering which is better and would be faster for my Mac. What are the differences between those two discs? 2. If I reinstall the system can I just copy back my entire iTunes folder to the hard drive and iTunes will automatically read it, all my playlists will be intact etc? Because I have a lot of FLAC files in my library which iTunes does not natively support and it would be a PAIN to import them all back in, album by album.