This is a mess : ) ! And lack of information too (especially system configuration, notebook or not, one hard drive or more, live CD Ubuntu or installed one), but I'll try help.
This doesn't look like an Ubuntu problems, since it doesn't affect BIOS. Shouldn't at least.
Furthermore as far as I know currently Ubuntu 13 is a beta version and 12 is a released version. Beta version may be not a good choice while having additional problems.
The Hard Drive and opening BIOS options in UEFI
We are assuming that the hard drive isn't paralyzing the system, but it may be the case. Some system won't even enter BIOS with a broken drive, while (presumably) waiting for its' response. In that case
1) Can You enter BIOS without any hard drive?
2) If not, are You sure that Del key is working and You're fast enough with the pressing? It worked before using Ubuntu, right (sounds weird)?
3) If You're experienced and it won't cancel warranty, reset the BIOS settings manually (disconnect power source and computer's power battery, remove motherboard's battery for 30 sec and put it back in) which by the way commonly speeds the booting up and more. Risky for notebooks since those commonly have hidden batteries. Mean!
That pretty much is all I can think of having provided info and at this point You should have entered BIOS, know what is wrong or have other ideas.
Win7 GRUB detection
What I deducted is that You just took a hard drive with Win7 installed on it from one computer and put it into another. GRUB won't see Win7 until You tell it to, the easiest case is to run
sudo update-grub at the
terminal, but making sure that GRUB options are set correctly may be needed first. There is a plenty of GRUB help in this website and You're having the best info to find what You need. But even when Win7 will be detected it won't have installed drivers for it's new location - new computer, so it shouldn't work all nice, if at all. Because Windows is not meant to jump around different computers and not prepared to.