How to add an ssd drive?

[joe at actionline.com]

Brian Cluff last wrote:
> You'll enjoy that Laptop a lot. I just picked up a T420 myself
> a few weeks ago and everything works perfect right out of the box.
> I did add 8 gigs of ram for a total of 12 and installed a 240Gig
> mSATA SSD ... an addition to the 320 Gig spinning drive that
> I put /home on, and that made a huge difference in the speed
> of all the apps loading.

How difficult is it to add an SSD?

I really don't need the 500-gig HD that is in this T420
that I just bought. On my old net-top system, df shows this:
Filesystem     1K-blocks     Used Available Use% Mounted on
/dev/sda5       15307020  6231552   8307468  43% /
udev             1020708        4   1020704   1% /dev
tmpfs             412276     1060    411216   1% /run
none                5120        0      5120   0% /run/lock
none             1030680    21072   1009608   3% /run/shm
/dev/sda6       71559236 26600696  41374540  40% /home

Instead of flushing the 500-gig HD, could I just install
a 64-gig or 128-gig SSD and install Linux on that and leave
the 500-gig unused? I don't need to bother with dual boot.

I looked on Amazon and saw these:

Transcend 64GB SATA III 6Gb/s MSA370 mSATA Solid State Drive
(TS64GMSA370) by Transcend $39.99 Prime

MyDigitalSSD 128GB 50mm Bullet Proof 4 BP4 50mm mSATA
Solid State Drive SSD SATA III 6G - MDMS-BP4-120
by MyDigitalSSD $55.00 Prime or $44.95 used (3 offers)

Also, what is the best way to install Linux Mint 17.2?

I downloaded linuxmint-17.2-mate-32bit.iso but the size
is 1,572,864,000 so I can't burn that onto a dvd to
install it.