Since you have no idea whether you will have a functioning mouse...or not...and there is data you want from it i suggest using an external laptop drive enclosure to retrieve your data...
See if someone you know has one...if not a decent one is about 35 Bucks.
You want one with an A/C power adapter as USB can be flakey at times for power.
Then you simply remove the HDD...again find someone who knows how...insert it in the enclosure...then hook it up to a working desktop and copy/save all your data...
Then replace the HDD in the laptop and turn it in for a Warranty claim.
At this point it would accomplish nothing to reformat it as you don't know if the hardware will work properly or not.