From basic computing theory, when a computer OS is doing 'nothing' the process that allocates tasks allocates a 'process' called 'idle' to run, so that the computer doesn't lock up! The processor is either 'working on a task' or 'stopped waiting a task to run'.

Usually it does 'nothing', but on big grunt boxes, it can be organised to do 'useful things' like calculate Pi to 1 million decimal places, etc.

Now a 'spooler' is a process that waits for input from something and queues it up to feed it somewhere, usually things like gathering output from 'printing jobs' and feeding it to a 'printer device'.

Malware can infect many things, and pretend to be 'normal processes' - they can infect you by means of 'trojans' and 'worms', etc.

If you run the various scan things and have a firewall, and do the necessary things that stop malware form getting your system, then the processes should be 'standard' - the fact that an 'idle process' show a high usage while 'nothing else is running' is not of itself a cause for worry.

As for 'spoolers' - the Win9x systems used to have a way of NOT running things like spoolers until they were 'needed'. That said, you need some sort of 'monitor process' running that can detect the need to start such other processes.