I have broken it

[bishen67]

Firstly i am a techno moron,so please answer simply. My computer takes ages to start up and shut down. It freezes after a few moments use,the hard drive light seems to be on permanently.I think it is caused be me doing something,i cannot remember what,and the question asked was something like ,"how much resource do i want to allocate",instead of leaving well alone,i entered a figure.I am wondering if i have given it too much memory,and there is barely enough to run a normal system .Looking up troubleshooting it suggested to remove old system restore dates which i did. Wrong move. I have uninstalled all the rubbish i have installed,but need someone to tell me how i can now find out what i allocated all the memory too and how i can restore it. See ,i told you i am a moron.