Falion, many thanks for that detailed post. I guess I should get more RAM, but with no income presently, I guess I'll just endure it. Anyway, I don't usually play AI more than 1-2 missions at a time.
As for your list of free programs, I've downloaded the CCleaner and the a-squared program. I'm also using Spybot, but since you've recommended a-squared, I'll remove it. Teatimer takes up quite a bit of memory. In addition, the AV that I'm using is Avira AV Personal and Zonealarm firewall. Is a-squared Free an AV? If thats case, I can replace Avira, which always lags the CPU while updating. I also have Windows Defender installed and regularly updated.
I also just installed a program called RAM Idle LE which is supposed to improve system performance, does anyone here use that?
Lastly, I have a question about CPU performance. Under the XP task manager there's a number at the bottom right hand corner that says Commit Charge. Before I play AI, the maximum is usually 450-550/920M, but after playing AI and returning to a laggy Windows, the maximum 'charge' goes from 920 to 1000+M. What does this mean?
Thanks again for your advice.