Will a new 13" macbook pro actually be an upgrade? And what is wrong with my imac?

[pne]

Hi guys, I am looking for a new laptop primarily because I want to edit 4k video shot from my gopro and S7. I'm currently using an old 2009 iMac 27", with i5 2.66ghz 4GB ram, ATI Radeon 4850 512mb graphics card, and a HDD.

I don't understand much about computers, and every few years I get sucked back into trying to research and learn about the latest specs and names of processors. And it seems like I have to wade through a lot of marketing and BS to get to the real numbers about how much faster a new computer will perform. Anyway currently my imac is pretty pathetic, it takes a full 1 minute 20 seconds to launch microsoft word to load a blank document. Similarly launching the photos app takes 52 seconds to fully load. Mail takes 30 seconds. What the hell is going on with this thing? It's running El Capitan and I don't install much software on it, I only use it to surf the web. Why does a word processor take over a minute just to launch? At times I am actually getting lag on it as I type!!

I ran geek bench 4 on my and got a score of 2500 single/ 6790 multi. This is in the ballpark of laptops I'm considering like the 13" MBP. My question is, does this mean my desktop has the same computing power as this laptop?

 

[BadAsAl]

You can use passmark.com to look up your processors and video cards and get a score for each. This helps you quantify the difference in performance.

Your iMac has an i5-750 processor that gets a score of 3724.
It has a GPU that gets a score of 1034
The slowest 2015 MacBook 13" has an i5-5257u that gets a score of 4337.
It has a GPU that gets a score of 955

So yes you are going to see similar performance.

Sounds to me like your iMac needs some maintenance. I would:
try these first:
Reset PRAM
Reset SMC

Then:
Shut the Mac off, and start it up again while holding Command and S. You’re launching Single User Mode. You can release the keys when the intimidating black screen with messages in white text appears.

Wait until the command-line prompt appears, when all the text is done scrolling past. Then, you’ll type fsck -fy and hit Return. And wait. Possibly for several long minutes.

If you get anything other than a message that it seems OK, then run the fsck -fy again until you do.
Once done, type reboot and hit enter

Check your disk space under disk utility while booted and see if you are close to running out.
Find a temperature monitor program and see what your system temps are, if they are running hot that can cause issues.