MacBook - Trouble Waking from Sleep

Hey everyone - newbie here. I have a 13" MacBook, Aluminum, late 2008. OS X version 10.7.3. 2GB memory, 750 GB hard drive (511 GB free). It's in great shape and I've had few problems with it until recently. (Most are related to the Lion update a few months ago, but that's a different story.)

In the past week or so, when I open my MacBook from sleep, the screen does not activate. It doesn't respond to key or mouse actions. Usually it only responds to my pressing the power button quickly, and it will wake after 3-4 seconds. Any ideas what may be causing this and/or what a potential fix may be?

Thanks in advance! Kelly

Try resetting the SMC to see if that helps. See this Apple KB article. LINK Also, make sure you obtain the supplemental update to 10.7.3 from software update.

Thank you for the suggestion! I'll give it a try tonight. My machine is completely updated as of yesterday, so hopefully your suggestion will work... I'll re-post if it doesn't. Thanks again.

Kelly