Firstly, the "partition merging" question you ask. There is no "merging" of partitions - the actual 'merging' involves deleting a partition completely and then manually expanding the partition (in layman's terms). Because there is no 'merging' of partitions, your question on it is going to be answered with a "No, there will be no merging of partitions". I do not reference merging later on in this question because there is no real 'merging' of partitions.
As well, in the original quesiton, you actually have only two physical partitions: the 234GB one, and the "Extended Partition" - inside the "Extended Partition", the partitions are logical, not physical.
If you want to expand an existing partition, then you have to have free disk space adjacent to the partition you want to expand on the disk. You would have to delete the existing partition, and either expand your "Extended Partition" to take up the free space (then move the partitions around inside the extended partition in order to resize whichever of the partitions you want to expand).
The breakdown of what is what on that window is as follows:
(1) Erase - This is just deciding how you want to format.
- Quick just nukes the beginning part of the partition which defines what is where on the disk, but leaves the actual content of the rest of the data in the partition intact. If you forensically examine the disk data with a hex editor, and the right tools, the data can be retrieved fairly easily unless data has started to write to the partition. (Then, most can be recovered, depending on how much data has been overwritten).
- Use this if you do not believe the disk has bad sectors.
- If you use the slow method, it fills the 243GB partition completely with zeros (at the byte level) before creating a new partition. Done correctly this can literally destroy the data that was in the partition. (This is effectively how brand new hard drives come - completely filled with zeros, except perhaps for the boot record section, which is not relevant to this question)
- Use this option if you believe the disk has bad sectors and is the cause of the damaged Ubuntu installation.
(2) Type is the filesystem you want. Choose this based on compatibility with other OSes if you have more than just Linux on your system. If this is an Ubuntu only install then use either
fat32 depending on your needs (which is based on the size of the files you're storing there). (NOTE: These descriptions are better worded in the window on the 14.04+ version of the 'Disks' utility)
ext4 is Linux compatible, and prevents Windows/Mac compatibility (for the most part).
ntfs is Windows and Linux compatible (but does not work nicely with Macs). If you need a lot of data storage and Windows compatibility, use
fat is actually
fat32 format. This format is compatible everywhere on most every device, but only supports files up to 4GB in size.
fat32 is also able to support partitions up to 32GB in size, but any larger will not be supported.
(3) Name is just the label on the disk. Name it whatever you want but keep it relatively short (9 - 10 characters at most). (This is how you can name Flash Drives - by applying a short label to the disk. Same applies to actual hard drives too. It's mainly just for show or to give you a description of what the disk is for.)