what didn't you understand about the word development ?
where exactly does it crash ?
remove any "fastboot" from menu.lst and appendif it's not caused by a crash from upstart or gdm, etc. it should be "fixed" temporarily,Code:scsi_mod.scan=sync
after that wait some days and update your system and try again whether it boots fine without those settings
I have seen Ubuntu make some improvement in boot times over the past two releases. My systems now boot in under thirty seconds, but since I do not have hot hardware, it's not quite down to the sub twenty second level; twenty five seconds is the best time I have seen from GRUB to GDM login screen.