Will adding RAM to my Mac Mini make it run faster ?

Question

Hey all,
Since I upgraded to Mavericks, I've started having two issues with my Mac Mini (mid-2011 edition, with 4Gb of RAM and an Intel i5 processor at 2,5Ghz)
1. I use FileVault so I need to login as soon as my machine will boot. Unfortunately, after the upgrade, the layout of my keyboard switched to US. So every time I login, I need to type my password in as if I had a qwerty keyboard. Apple is well aware of the issue which is reported on many forums but still hasn't released a patch yet. That's a nice middle finger shown at their customers, but I guess this is customers service the Apple style.
2. Next, I have a more embarrassing issue. My Mac Mini has become so slow that it has become almost unusable for many common tasks such as managing my photos in iPhoto or just surfing the web with Google Chrome. I noticed that doing almost nothing on my computer, I always at 3,5Gb and up of memory usage. As I'm typing these lines, I only have iPhoto and 4 tabs in Google Chrome opened and the "Used memory" line in the activity monitor says I'm using 3,99Gb of RAM.
So here is my question :
- Could the lack of RAM be the main reason my Mac Mini is extremely slow and often freezing on commons tasks (iPhoto and surfing the web) ?
- If so, would upgrading to 8Gb  of RAM make it noticeably faster ?
Thanks !

Answer 1

According to the image of memory usage you posted, the Virtual Memory is taking 5GB of HDD free space to run (whatever was on, in the image) and the physical RAM was nearly all taken, with 3.99GB in use. Most of the items in the far right side appear to be other usage, some in MB. Where is that being used?
{Not certain what to make of the other usages, because it is easy to forget what I saw when it isn't english. But I do understand several written languages and a few listened-to, even though I don't speak them. Even some dialects from Asia if I see the speaker. Except cyrillic Rus, greek, & a few others.}
Given the RAM is the least expensive way to add performance to a machine with hungry operating system and applications that also won't go unfed, this aspect and a good deal of unused or 'free space' in the hard disk drive both add up to better performance. Less RAM than optimal is a bottleneck, as would an overly full near capacity hard disk drive; when running on a slim margin.
Other browsers to consider are Mozilla-derived FireFox, Seamonkey, and iCab. Maybe Opera.
Good luck & happy computing!