Linux – Installing Ubuntu to dual-boot from mSATA

So you want to have your old installation of WinXP on the old drive and on the new and fast SSD drive Win7 and Ubuntu 12.04. Ok, then the safer way to proceed is:

1. remove the old drive and install the new SSD drive
2. partition the new SSD drive (e.g. using a livecd or even better a USB pen with gparted) to have (at least) three partitions. The first NTFS, the second ext3 or ext4 and the third swapspace.
3. install Win7 on the new drive
4. add to the system the old drive
5. (optional) repartition the old drive to host a ext3/ext4 partition to be used as storage for huge, disk-hungry programs (e.g. eclipse, matlab, etc.). This will somehow load-balance the disks usage without the need of a striped raid. If you don't plan to dismiss your WinXP soon and if you think you'll need a similar thing on Win7, create also another NTFS partition.
6. install Ubuntu on the new drive, indicating the newly created swapspace and the new disk's MBR (/dev/sdx - grub2 doesn't love to be installed inside a partition) as destination for the boot loader.

Without more information, any answer will be guesswork. I recommend you boot from an emergency Linux disc, run Boot Info Script, and post a link to the RESULTS.txt file that it produces. This will provide information about your partition layout and boot loader configuration.

Contrary to what TheX wrote, Ubuntu most emphatically does support (U)EFI booting. TheX is confusing UEFI with one of its specific features, Secure Boot, which is intended to improve security. Ubuntu has supported (U)EFI for quite a while, and they're working on seamlessly booting on systems with Secure Boot enabled. They may even have incorporated such support in Ubuntu 12.10, but I'm not positive of that.

Edit:

Your system is definitely not booting either OS in EFI mode. Both your hard disks use the MBR partition table, and Windows ties the partition table type to the firmware type, with MBR being superglued to a BIOS-mode boot. You also have no EFI System Partition (ESP) or FAT partition, which are required to boot UEFI-based PCs. Thus, your suspicions about a mixed BIOS-mode/EFI-mode boot are misplaced.

My hunch is that you've accidentally changed a firmware setting -- perhaps you've enabled a "fast boot" option or changed the splash screen. This will affect how the BIOS goes through its initial tests and displays, and could make it harder to access its settings or activate its boot manager. I recommend you go into the BIOS settings and look for such options. I'm not familiar with your specific model so I can't give more specific advice on this score.

Once you've booted Ubuntu, you should be able to get it to detect your Windows configuration and add it to the GRUB menu by doing a grub-mkconfig -o /boot/grub/grub.cfg. If Windows still doesn't appear in the GRUB menu, you may need to create a manual entry for it in /etc/grub.d/40_custom; or you can use your BIOS options to select the boot device, as you've done in the past, if you can slow it down to the point that getting to those options can be done reliably.