Hi! I was working on a really cool wallpaer, then next time I restarted my computer it can't boot!! I think I have deleted a boot file. And even worse: my DVD is broken and I don't have floppy!
But can I use an extern usb dvd drive to boot a recovery disc?
you should be able to yes. I think you need to tap f8 or one of those things to select your boot menu....then you will have the option of where you want to boot from
But does bios automatically detect the usb-drive when I start the computer? Does external drives have plug and play?
You have to have a newer BIOS, and you have to set the first item in the boot order to USB-CD.
if you have a mac you can boot your computer into target drive mode holding t after you click the power button
Damn I don't have that. I guess I'll have to rip my laptop hdd out and plugg it to my desktop. I also have an essay stored in the hdd which has to be handed in within a week. 
Like liquidplasmaflow said, it depends what version BIOS you have. Considering you don't even have another form of input, it's probably too late to add USB-supported BIOS if you don't already have them. There's no point in not testing it though--like Photo said, you have to hit F8 (it's either F8, F2, F5, or F12 depending on who manufactures your machine)
When you say DVD, do you mean CD too?
-NC
USB CD and DVD drives communicate with the computer on the same basic level; the BIOS would recognize a DVD drive just the same as it would with a CD drive.
Yeah, but his DVD drive is broken (and it sounds like that's independent of the computer problems), so I was asking if he had another internal CD drive that he could use.
-NC
I have a laptop, so it's CD-RW/DVD-RW together. My bios only supports network, hdd, and cd-rom as boot.
I'll go to the hardware store today and look if they have an IDE-adapter from 2,5" to 3,5" HDD.
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