FC4->FC5 upgrade problem
 

I followed some instructions, so that I could update the FC4 to FC5 via yum, but somthing got wrong and I cant access FC4or 5?! after rebooting. In the boot loader there are 2 (!) fedora core what happened? My computer is an emachines t641, and it has windows xp too, from where im writing right now. (common windows savin linux? this is wrong!). Do i use the rescue cd?

You could use the rescue CD, or you should be able to update via a FC5 CD. It should recognize the linux partitions currently installed. As far as I know, it is still recommended to use the CD to update rather than yum, especially if you are using LVM.