possable

Is it possable to repair my existing Windows XP from the bootable disc rather than installing a fresh copy of Windows...? if it is possable then pls tell me how will i do that...? i think i have a problem in my current OS specially when iam playing FIFA 07 after about one or two match suddenly...

like mouse, can we increase or decrease the sensitivity of our keboard, if it is possable then plz tell me how...?

is it nessesery to limit the upload rate of utorrent to a certain limit if yes then tell me what should be the limit; whyle downloading a file through Utorrent it donot upload anything, uploading start only after the task is 100% compleated, is there any possable possable way through which...