Well, being a n00b to linux entirely.. you may want to take my advice with a grain of salt.
Firstly, I ran into the same problem with grub boot selection, regarding not fitting into memory so I hear it has to do with where the boot-partition is on the hardrive (physiscally). Lilo however works fine.
I've been running my mouse using a usb -> ps2 adapter due to the fact I'm beta testing a couple things which have problems with usb currently. So, recently I decided to switch back to usb.
Poof, system hang on boot when "detecting module dependencies"... unplug the mouse and it cruises by just fine, same as always.
Just figured I'd add an observation, as I don't really want to switch my mouse back to ps2 I'm still stumbling along trying to find a solution.
I'm using the asus a7n266-c
If anyone figures anything out regarding the problem, please let me know.