Upgrading old laptop, processor or memory?

I want to upgrade my laptop (small project):
Current: AMD Athlon XP 1400 1.4GHZ, 1GB RAM, 60GB hard drive.

I would be interested in what brings more:

Processor upgrade to 2 GHZ.
(I already know that I can replace it, the question is whether I shouldn't have a problem with myself? (Cooling)).
(The processor only costs 5 EUR, so there's no harm if it doesn't work)

Do you have to pay attention or is it plug and play?

Or the IDE hard drive against an SSD (MSATA with adapter to IDE)
(MSATA is there, adapter has to be bought for 5 EURO)

I would recommend upgrading cpu and ssd.

There are different sockets for the CPU if you know that you need an adapter for ssd ok.

It can't be anything rational when it comes to price performance. The costs are probably ten times as high, so I'm not going to deny you the fun of free trials now.