another upgrade question

I've been really stupid and bought an iphone 4.. and I have a 3.5 yr old MacBook like this:

Model Name: MacBook
Model Identifier: MacBook2,1
Processor Name: Intel Core 2 Duo
Processor Speed: 2 GHz
Number Of Processors: 1
Total Number Of Cores: 2
L2 Cache (per processor): 4 MB
Memory: 1 GB
Bus Speed: 667 MHz
Boot ROM Version: MB21.00A5.B07
SMC Version: 1.13f3
Serial Number: 4H648J3YWGL
Sudden Motion Sensor:
State: Enable

And it won't talk to my iPhone. Doh.

Question is - can I install Leopard, or Snow Leopard or Sleeping Pussycat or whatever the best OS is called?? And if I can, is it easy to do and not likely to kill all the stuff on my little laptop?

As you can tell I am a total idiot when it comes to techy stuff. I just expect them to work. Apple has never let me down until now and I feel both daft and slightly cheated as I didn't read up about it enough and wasn't warned by the guys in the apple shop here.

Save me please.

Upgrading

Yes, you need at least Leopard or 10.5.8 or later to use the iPhone 4.

Snow Leopard is only a minor upgrade from Leopard, so I would go straight to Snow Leopard if I were you.

You don't specify what version of Mac OS you have already.

As for upgrading you can do three ways: Upgrade, Archive or Install as in this article:
Upgrade Mac OS X to Leopard

I'm using 10.4.11

I'll have a look at that link. Thanks!

Someone mentioned that if I was using such&such a processor then I couldn't upgrade to Snow Leopard and I'd have to just get Leopard??? Is this not so? Or is mine ok for Snow Leopard?

God I feel soooo out of my depth. Think I'll revert to blackboard and chalk..

People who have PowerPC-based Macs (G3/G4/G5) cannot upgrade to Snow Leopard.

You have an Intel Mac, you are good to go.

Cheers Chas!

And if I don't have enough available disk space, presumably I can just trash a load of stuff I no longer need?? (see I am a complete idiot!)

If you don't have enough disk space you should make some, or get a new HD.
OS X really doesn't like anything less than 15-20GB or more free space.
Filling up your HD is asking for trouble, often irreparable damage to your OS.

Not only "what 6string said," but installing Snow Leopard over Tiger will actually DECREASE the size of the system, ie freeing up space! Now that's progress!