Best way to upgrade MacBook from Tiger to Snow Leopard? I only have 1 GB RAM

I'm currently running the latest version of Tiger (10.4.11) on my Intel MacBook with 1 GB RAM, and I want to

upgrade to a later version of OS X. I understand that Mountain Lion requires 2 GB RAM, so I'm thinking that

I want to upgrade to Snow Leopard (10.6). What's the best way to go about this -- where do I get the upgrade, etc.,

and what do I need to watch out for in terms of compatibility with existing applications such as Microsoft Office?

Thanks