What OSX does suit better for PowerBook G4 17"?

I have 2 partitions, both as StartUp Disks with Leopard 10.5.8 OSX.

Can you please tell me what OSX is better for my Mac? Leopard or Tiger?

I never tried the last, 'cos I bought this laptop a second-hand with Leopard on it already.

So, I'd like to know more what of the OS is better for Powerbook G4 (concerning productivity, speed,usability etc.)?

Here's my Hard Ware Overview:

Hardware Overview:

Model Name: PowerBook G4 17"

Model Identifier: PowerBook5,9

Processor Name: PowerPC G4 (1.5)

Processor Speed: 1.67 GHz

Number Of CPUs: 1

L2 Cache (per CPU): 512 KB

Memory: 2 GB

Bus Speed: 167 MHz

Boot ROM Version: 4.9.5f3

Serial Number (system): W8******SX0

Hardware UUID: 00000000-0000-1000-8000-00145122650A

Sudden Motion Sensor:

State: Enabled

I'm asking, 'cos sometimes (especially now) the System really slow! Even writing this text is no really easy task to do!

Productivity of the laptop harshly decreases! Launching applications, opening windows, writing text, opening tabs in a browser etc.

<Edited by Host>