I have multiple doubts here. Its a Seagate 500GB 7200RPM HD. I had installed it few months back after my original Laptop HD stopped working. The current drives on my latop, as shown by the Windows Disk Management are:

After installing the new HD, I had done a complete clean install of Windows 7 and I didn't create any parition myself, manually. So there are 4 drives. Even previously, before I installed this new HD, my laptop had 4 Partitions. But the there were no un-named partitions like the two in this case. The other two were HP tools and Recovery or something. It was pre-configured, Factory installed Windows.

Also, now when I right cick on the unnamed Drives from Disk Management, all the options are greyed out (see image) except the delete partition image.

1. So how do I know what's inside those partitions?
2. Will it be ok if I delete them?
3. I want install Ubuntu and dual boot it with my current windows installation. I cannot do it in current setup as there are already 4 partitions of my HD and if I will try to make a new partition, it will be a logical one (correct me if I am wrong here). So can I delete the un-named, hidden partitions and use them for Ubuntu?
4. A bit unrelated question. As a backup option, can I use the Windows 7's Backup and Restore facility to keep a complete backup of all the drivers and system softwares.