I find using gparted much easier for this, since it shows the actual layout order for the partitions. Using gparted, I would probably delete sda8 and sda6, and leave sda5, which is already at the end, and edit fstab to use sda5. Then it's easy to grow sda7 to use the space above it that was being used by the swap drives.

To edit /etc/fstab is not hard; if you don't know how, I can tell you the details, but the basic drill is to run sudo blkid -c /dev/null in a terminal to get a list of all the UUIDs. The addition of the "-c /dev/null" just insures that it doesn't use a cache, so you get any recent changes. Once you get the UUID for sda5, simply substitute it for the existing on in your fstab file. You will need to edit it using sudo, and a text editor such as gedit or vim.

Lines starting with "#" are comments. The line to change will look something like this:

# swap was on /dev/sda8 during installation

UUID=000-0000-0000-0000-00000000 none swap sw 0 0.

The UUID (shown as all zeros) is made up of hexadecimal digits (the letters A-F, plus numbers). The results of blkid will look similar

To delete the swap file, you may need to disable it (right-click and select swapoff in gparted).

EDIT: More details for user.

You will need to use a live CD with gparted. Either the gparted lived CD or the install CD will work. It's pretty easy, actually. The first thing to do after running gparted is to select your disk drive in the upper-right, if it's not shown. It may be

You will see a representation of your disk layout at the top of the window. You should have all 3 swap drives at the end, on the right, labeled sda8, sda6, sda5. The numbering isn't by position. To grow sda7, you need to have space adjacent to it, so you will not delete the swap drive furthest to the right.

All you have to do is click on the partition, either on the top graphic, or the list below. The swap drive will say "Linux-swap" in the column for File System, and there's really no danger of deleting the wrong swap drive, unless you're really low on memory, possibly. In fact, I just discovered my swap drive has been disabled for a while.

So, right-click on each of the two near, but not at, the end (leave the one at the end) and select "Swapoff". You should then be able to delete them when you right-click. Then, right click on the main sda7 partition, and select "resize/move", and then grab the right-hand side and drag it as far to the right as you can.

This doesn't do anything yet. You have to select "Apply all operations" from the Edit menu, or click the checkmark toolbar button. That's it.