For the first minute or so when I wake up my 2007 MacBook, it becomes really laggy. I have iStat installed and it usually shows the CPU and memory usage as being very low, but sometimes it jumps up. Either way, for a minute or so the computer's pretty much unusable. Just now I took it out from sleep mode and the CPU usage did go high and general performance was very slow again. The apps I usually have open are Firefox and Chrome. The OS is Snow Leopard with all the updates installed. I've tried repairing permissions and rebooting but no help.