Unfortunately... as you've now found out to your cost... doing a 'clean' install yourself, completely wipes the hard drive.

And having wiped the hard drive, there's no way to restore it to the pre-installed configuration.

What you'll have to do now, is create your own [extended] partitions.

It's not difficult (Google the subject, if you don't know how to do it already.  Try here for starters though), and in fact it's somewhat beneficial, because with the hard drive set up as per Dell's configuration, you couldn't add your own partitions, without first deleting one or more of the Dell partitions!

That's because Dell don't allow (for reasons unknown to me?) more than four partitions?

Having since wiped the hard drive however, you're not limited to a specific number of partitions.

Let us know if you need any more help on the subject?

i dont mind having jus one partition with the os and all other files  but does it affect system peformance and when i deleted the other partition would it of deleted completly from the system or would i hav had to format it first cuz the main reasen i done a clean install was  because i had a trojan and i wanted to make sure it was gone could the trojan still be around ive done a kaspersky scan which was the one that originally found it and it is coming up clear now i blame mcafee for this i had the total protection and it let stuff past and didnt even detect them when i scanned