After a lightning strike, my brother's computer has been left unusable. He took it to a computer repair shop who said the motherboard is probably faulty and they gave him a quote to repair it.

However, the computer is 4 years old and he'd been wanting to get a new one anyway. So rather than replace the motherboard, he was wondering if there is a way to remove the hard drive from the broken computer and access it via his other computer?

It sounds like it should be pretty straight forward but could anyone advise if this is relatively easy to do and how to go about it? I have suggested to him that he may be better off letting the repair shop replace the motherboard.

His broken computer is a Dell 2400 and the computer that he wants to attach the hard drive to is a Dell 3100.

Yes this is quite straightforward.
Assuming that the drive is all right, it's a simple case of pullig it out of the old box, change the jumpers on the back to SLAVE and insert into the new box.
Windows will assign a new drive letter for you and you should be able to get any data off it.

Thank you for that reassuring news Curlyben :)

Will it be fairly obvious how to change the jumper to SLAVE? i.e. is there a switch or does it have to be done via the bios or something?

(Bit of a novice here regarding the inside of machines in case you could not tell! I have done techie things before but it always takes a long time to figure it out and any guidance would be gratefully appreciated!)

No worries, but bear in mine this is an IF as the strike may of fried your drive.

Now the jumpers are on the back of the drive and it's basically a small bridge.
Quite easy to find and most drives have a small diagram to tell you how to set them.

Thanks very much for your help - got it sorted! :-)

Excellent.
All good then.