Ive got a dell dimension 1100 using windows xp home its very slow and the screen



could you please advise me on what to do to resolve this problem please.
Start by entering the board bios and be sure the "fast boot" option is enabled; then use the windows disk clean program and check off all the categories. Then check your drive with anti-virus software. I use microsoft malware; spybot is free. When you're done, use cpuid to check your ram specs and see how much is being recognized. If you're still not satisfied, then a format will give you the best results, but be sure to have all your original device drivers handy; xp needs the motherboard cd or oem drivers installed separately. Vista or 7 may find all the devices without using a separate cd.