Whitey is dead.
The $999 laptop is now the 11.6" MacBook Air. MBA, MBP and rMBP are the only laptop models currently.
You can still find refurbed latest generation whiteys for around $500-$600, though they are quite a bit behind current MBP models in terms of performance, especially graphics. Even the 13" MBP model, with no discrete graphics, will significantly outpace a 13" White MacBook with it's integrated graphics alone.
I think you'll be very happy with a new MacBook Pro. It sounds like you aren't willing to really tear this thing apart and mess with it, which is fine. Chances are, you'll find out it's not repairable anyway. If you are willing to replace it and upgrade, that's probably best.
If the extent of your computer usage is facebook, media consumption, etc. Then go to newegg.com and order one of the Core2Duo 2GB RAM MacBook models they have, and pick up a little extra RAM as well to help it better handle modern applications. Heck, you could even throw an SSD in there as well and end up being cheaper than a MacBook Pro, with pretty decent performance.
If you do things that are a bit more complicated than that, including any gaming, photoshop, audio production, etc., then you will really benefit from the Core i5/i7 architecture of the new MacBook Pro models.
All that aside, if I were you, I would at least attach an external keyboard just once, and perform the SMC reset using that. If it turns out that this fixes all of the issues, you can still upgrade your MacBook, but then you'll have a nice backup or second system! I like to use old systems as home servers or as media devices plugged into a TV (to stream Hulu, Netflix, etc.)