@multi
Download Advanced Task Killer(ATK) from android market. After the installation is finished, restart your phone.
After restarting, open ATK and put the processes like music player, gallery, messages etc in ingore list by long pressing them and selecting ignore. Starting an application again and again utilises a lot of CPU, so let the important tasks remain in ignore list.
Put an ATK widget on your homescreen,so you can kill tasks after performing your work.
If you dont want real time syncronizaition with your gmail, put auto sync off. Otherwise it will make connections with gmail every now and then.
This things works with me, make a try and may be they will work for you too...
And yes this phones takes a load of time to charge. It take about 3hrs to charge completely...