Completed wrecked my Macbook Pro! Please help

Question

Alright, this situation cannot be understated, my macbook is completely wrecked, and I desperately need help.
I'm not very "tech-savvy" and am not too sure on all the lingo, so please bare with me.
Earlier today, I installed Windows XP Proffessional 2002 onto my MacBook Pro, I did not do this through bootcamp as it wouldn't allow me to. Now after I installed it, I could only use Windows. I presume that I must have overridden the OS Lion paritions (whatever these are). Now, I managed to figure out that Command+R thing, and have run into more problems, when I go through the install thing, it then says at the end to chose a disc.
The only option is called untitled, however this says: "This disc doesn't use the GUID Partition Table Scheme, and basically says I can't do it.
Now, after some searching I was told to go into Disk Utility to resolve this. I will explain what I have in disk utility.
The left side looks exactly like this:
500.11 GB Toshiba MK5065GSXF
       Untitled
SuperDrive (Greyed out)
disk1
     Mac OS X Base System
Apparently on the 500.11 GB Toshiba bit, it should have the Partition Map Scheme as the GUID thingy, however it has "Master Boot Record".
The "Options" inside the partitions tab is greyed out as well, and cannot be clicked.
Also, the other option is to restore from a backup, however I never made one. My mother also has a Macbook Pro, would it be possible for me to backup hers and use that backup?
Please somebody help me! I don't know what to do and I'm freaking out that I've broken it.

Answer 1

You need to boot using Command+r again and then use Disk Utility to erase that Windows XP partition and more then likely Repartitioin the complete drive. As I think the Command+r you are using is booting the computer from the Apple internet servers using the Online Lion Recovery HD system. Because if you Re-Partitioined the drive to install Windows XP and do not now have the drive set up with a GUID partition table you can not have the Recovery HD partition on your internal drive. Then format it Mac OS Extended (Journaled) and give the name of Macintosh HD, Click the Option button and make sure the drive Partition Table is set to GUID, then click Apply.
Yes that will Wipe Out the Windows XP you installed (which In My Honest Opinion you should not have installed in the first place. At least not to the Main hard drive).
Once that is done, finished, exit out of Disk Utility and Select Reinstall Mac OS X and click Continue. Have the computer connected to your internet Router by Ethernet cable when doiing all of this. OS X Lion install will start and when asked for the disk to install to select the Macintosh HD partition.
If you really need Windows maybe you should of bought a Windows PC and not a Mac. If you need to run Windows on a Mac you have 2 options.
1) Use Boot Camp to partition and install Windows 7 on your Mac as a Dual Boot System. Yes you will need to BUY Windows 7.
2) Use and of the three Virtual Machine software programs, VMware Fusion, Parallels or Virtualbox, and install any version of Windows into a Virtual Machine. Then you can run both OS X and Windows at the same time.
Of course there is a third option (If your Mac is Brand New). That is to Return it for full refund (Apple has a 14 dayNo Questions Asked return policy) and buy a computer, Windows computer, that is more for what you need to do on a computer. IE Run Windows and Windows Programs.
Good Luck.