ifixit.com

The Ifixit tutorials are usually spot on. Ram should be pretty straightforward, hard-drive a bit more fiddly.

print out the instructions, then as you remove the screes them tape the screws to that step of the instructions. That way when you reassemble you're able to make sure you've put everything back in the right place before you move on to the next step.

that the black or white plastic mac?

if so it's really really easy. the hardest bit is getting the L shaped bracket to fit back perfectly, and doing whatever you need to do to get the OS on to a new clean SSD/HDD.

Great tip maccruiskeen - thx.
Yes it is the black Macbook. you think it's worth a go? The compouter is still in great shape, just needs an update, can't run much these days.

Can anyone recommend where to buy a SSD and RAM?

http://uk.crucial.com/gbr/en is an OK site. (edited as I got it rong)

either Crucial website or Kingston
both have tools that will tell you exactly what works, but iirc it's any standard laptop SATA HDD/SSD (slides in to place), and any standard 2x 2GB laptop SODIMM RAM.
it's really obvious how to change them when you take the battery off and unscrew the bracket.
mine packed in years ago.

I've had good experiences with Samsung EVO SSDs. Amazon seems to be about as cheap as anywhere.

Crucial is a good shout for RAM.

Isn't there some compatibility issue with SSDs in early macbooks? I tried to upgrade but it turned out that certain SSDs don't work with certain drivers found in the white plastic macbooks.

Not overly helpful I suppose - just make sure you do your homework is my advice!

Yes its worth doing. You need to do some research on RAM as Apple generally understate the amount you can put in. Non matched pairs (eg 2+4 = 6 works and is generally cheaper than pairs as you change just one chip. Also older slower ram quite expensive now, faster chips will work but need to do some research). SSD makes huge difference, I like Samsung EVO. I have upgraded 5 machines now for myself and friends and family. There are a few different methods, I know prefer the Time Machine plus USB boot key method. You’ll need a small Phillips and a Torx10 too. Email in profile you can message me and we can have a call if you want, Hampshire based if you want a hand.

It's surprisingly easy - as someone who has had no training in pulling a MBP apart. I just followed the guides as folk have signposted above - paying attention to either have the instructions running on another machine, or print them out.

I got the various little tools in Maplin for a few ££.

Before you spend money you still won't be able to upgrade OS-X beyond some magic version (dependent on your product ID thingy)

That means you can't update stuff like Safari and plug-ins etc. etc.

I'm pretty convinced a lot of slowness is stuff that now crashes (I run Activity monitor all the tome for example to kill processes that stall) and this seems mainly using Safari but I can't get a version of Chome or Firefox as they are unsupported.

Worth thinking about before spending money ???

Yes, the plastic ones are stuck on 10.8, so you can't get latest iTunes, etc.

But if you're happy with how it works right now, then go for it - super easy on those, I've upgraded plenty of them in the past.

Maybe looking to upgrade it is not worth the hassle.
I do have my daughters Macbook Pro - which could be easier?

Will do some research, thanks again.