Assuming you have a Win 7 disk and not just a restore disk from Acer I'd always recommend wiping all the crud supplied with most laptops and putting in a clean version of the OS.
Watch out for which key to press for fresh install when you switch the thing on, the options always seem to flash by very quickly.
Only real disadvantage I can think of by not using laptop bloatware is not having the energy saving functions when you're on battery power but as V_R said you can probably download that part of the Acer software from their site if you need it.