Why is it so slow

Grr my computer id driving me nuts it is normally pretty fast, but at the moment it has been goign so slow admittedly I did have only 1gb left onthe hard drive LOL, but I cleaned a heap of stuff up and now now 15gb but it is slow slow slow. I have been trying to resist the urge to buy a new I mac but I tell you if this keeps up I may just get one LOL.

Here is a LO I did last night with photos from the xmas shoot