Making a harddrive from one PC boot in another

[delorean76]

About a month ago my grandma's 1 1/2 year old Emachines PC fried (I was told a bad PSU messed up the mobo and Celeron 2.6ghz CPU). It was cheap so it wasnt that big of a deal, plus all she practically uses it for is solitaire.
Around this time I had been considering to build my own PC for the first time so I figured I could give my PC to her, moving any good parts from her old PC into mine: Compaq Presario 2.6ghz P4. Our PC's are quite similar. I connected her 80gb Maxtor IDE hdd to my PC as a slave, just to make sure all the info was there, and it is.
After getting some help here, I purchased all the parts for a new gaming PC that will be arriving on 10/11 so Ive been getting my current PC ready for her and moving my parts that I'm keeping from the PC. The only problem I've encountered so far is figuring out how to make her hdd eventually boot on my PC. Being the newbie I am I figured if I set her hdd as the master it would magically boot up. After trying that out and reading around this forum and the faq's, I see thats not the case.
I found out Im going to have to make her hdd the boot drive, instead of my current boot drive using MaxBlaster from Maxtor. Is it as easy as creating that partition on her hdd though? Ive never created a partition, etc. before.
How will this affect my hdd? So far I've simply copied the 5gb of info on her hdd to my 80gb IDE master hdd and backed up my master hdd to my slave 80gb IDE hdd. If for some reason, after I make her hdd the bootable drive, that I need to make my current bootable hdd bootable again, can that be easily done? Will I have to somehow make my current bootable drive also bootable for my new PC?

Thanks for any help, this stuff has really confused me

 

[defakto]

You will need to install windows again. Windows does not like to move major hardware like a motherboard.

 

[Kek]

I have done it though. But with so much of the hardware being integrated on the new motherboards, it's probably just as fast to reinstall Windows as it is to uninstall the missing devices and reinstall new ones... maybe even faster.

I really hate prebuilt machines. They use evil proprietary things, like BIOSes. My brother's old machine had a similar problem to the one mentioned here. I was out of town, so he took it to a shop. The guy at the shop was stumped, he couldn't get an OS to install, so my brother took it back and bought a new PC. When I finally got my hands on it, I flashed the BIOS, and voila, I was able to install an OS! Hopefully it will work when it gets a new PSU. But yeah, finding a BIOS for a prebuilt machine might be more difficult, though I have no experience with that (I keep away from those). Did I mention that I hate brand name computers?

 

[delorean76]

You will need to install windows again. Windows does not like to move major hardware like a motherboard.

Will I have to do for her hdd and my hdd? I dont have the xp cd's since these were prebuilt PC's.
Dont I have to make a new partition or something to make the hdd's boot on another mobo?

 

[SirKenin]

Will I have to do for her hdd and my hdd? I dont have the xp cd's since these were prebuilt PC's.
Dont I have to make a new partition or something to make the hdd's boot on another mobo?

Ummm. Emachines come with the OS restore disks. This I know for sure.

 

[kirbyrj]

Ummm. Emachines come with the OS restore disks. This I know for sure.

Aren't they usually tied to the eMachines hardware? Some will let you install on other hardware, some won't. Some might need a serial number from the original machine or something like that.

 

[SirKenin]

Aren't they usually tied to the eMachines hardware? Some will let you install on other hardware, some won't. Some might need a serial number from the original machine or something like that.

Yeah, the only problem I can see is if they look to the BIOS. I'm trying to remember what that damn disk looked like, and I can't I can't remember if it was just an XP OEM CD or a restore disk. I think it was a restore disk. Ah crappola.