I wish you luck, but these devices are slow as hell - even slower if you remain with its basic specs of 1GB RAM.
I have one (see below), and whilst it and avast free 11.1.2253 work fine together, don't expect lightning speeds for anything not just the AV side.
- Acer Aspire One, Win7 Starter (32bit) 10.1", 1024X600 screen, 2GB DDR3 RAM, Intel Atom N255 (1.5GHz dual core) CPU and 250GB HDD. Bold denotes I upgraded to a 2GB RAM chip in the single slot.