I've actually cut the story short. It's a rather long read if it's important to know the entire sequence of events.
1. The laptop was bought under the school's promotion. It is from Acer and Windows Vista Home Premium.
2. As it is supposed to be used for school work, it came pre-installed with the "School's Image". The laptop came with Windows Vista Business with license under the school's name, along with other software that's needed for Java programming, networking etc...
3. My brother somehow locked himself out on the first day of usage by setting a password. Somehow he typed the wrong password twice...
4. He inserted the Acer Recovery Disc thinking it would restore to Windows Vista Business, Windows Vista Home Premium appeared instead.
5. He realised that C:, the only hard disc drive partition, is only 120GB... the specifications on paper wrote 250GB.
6. Thinking we've been shortchanged by Acer, we went into Disc Management and found that the rest of the hard disc is used as EISA partition.
7. Did some Googling and deleted the EISA partition using Diskpart in Command Prompt.
8. Formatted the unallocated space and named it D:
9. Installed Company of Heroes and Gears of War into D: to test the laptop

Testing took about 5 hours. :]
10. Restarted laptop as Service Pack 1 was installed later in the day.
11. When Windows rebooted, D: is gone. The space reverted to an EISA partition.
12. This time, we deleted the EISA partition using Diskpart again, but left it as unallocated space to see what happens.
13. Laptop restarted, but stuck at black screen with flashing underscore. No boot.
14. Inserted Recovery Disc to attempt to reinstall OS, Recovery Application said "No Partition, cannot install"
15. Inserted my Trusty Windows XP Home Edition with Service Pack 2 CD (WINDOWS XP FTW!) and learnt that C: has become the EISA partition. Therefore, leaving the hard disk with NO system boot which explains why black screen at boot.
16. Deleted the 120GB EISA partition and started from scratch. Partition drive into C: (50GB), D: (10GB), E:(The rest of it) D: was created at 10GB hoping that it would be converted to an EISA partition, like what it did to C: when it was the only hard disc partition.
17. Pending...
I'm not sure what Norton stuff it runs, I know it has Norton Internet Security but I'm not sure about Norton Go Back. Will go check it out once it finishes restoring back to "factory" configuration... Thanks