reset the tablet to factory default, then set up from scratch if that does not cure issues there is probably a hardware fault.
The trail of the cursor/mouse will be due to the refresh rate of the screen being set to a low speed or the pointer attributes specifically being set to that option.
The band at the top of the screen may also be a badly selected option. A hard reset really does appear to be the best option for you if you do not know how to alter screen / appearance attributes and can get no better information from a FIXYA expert.
see link below for user manual
Toshiba Thrive Manual User Guide PDF Download