My computer keeps locking up alot, and I keep having to hit control, alt delete, to end whatever is running....any suggestions?

The biggest suggestion is for you to list your motherboard, video card, sound card, size of memory, etc.; what software is running when it locks up; what kind of anti-virus and spyware programs you run and how often. In other words, your problem could be simple or complex depending on your equipment and software, but you have to list what is there for anyone to help.