Downloads keep locking up. Help

Hello everyone. I hope someone can help me. I am running windows xp service pack 2. I have 768 mb of ram. The problem started with my cd rom. Switched out and my computer still does not reconize. Than my computer became 10 times slower than dial up. I have dsl. I ran adaware, stinger, spybot, ewido and spyware program through netscape. Everytime I try to update adaware it tells me no updates, version 6. I thought I would download the newest version and maybe a virus scan. I disabled my firewall but all the downloads I try, lock up at 4% or less. Last evening It said 3 hours to download new adaware so I did that and went to bed. Tried to run this am and missing data from the program. Tried again and everything won't get pass 4%. I think I have a major problem somehwere but withour being able to download I'm stuck. Someone out there Please help. Thank you for taking the time to view this.

 

Maybe you knocked something inside the case when changing roms? What is your computer not recognising?

Check all your cable connections inside the case.

Also you could try doing a system retore to just before the problem started.