Need to remove bottom of Acer 5050 in order to replace the fan

SOURCE: ACER Aspire 5050 Overheats

You can do it yourself, but I do not recommend it,
I would first try buying a cooling pad for your laptop to see if that resolves the problem.

SOURCE: sound driver for Acer Aspire 5050

you can find it here
http://support.acer-euro.com/drivers/ftp/ftp.html

SOURCE: removal of cooling fan

You need to disable your laptop.
follow this step:

Remove harddrive.
1. on the back of laptop, there are 2 doors. open it all. 1 of them is harddrive.
2. remove harddrive.

Remove wireless cable.
1. open 2nd door on the back, you can see rams and wireless card. unplug wireless cable from wireless card.

Remove chassis
1. Remove 2 screws on the hinge cover, so you can remove the power cover (power cover is cover that have power button).
2. after you removed power cover, removed keyboard.
3. remove 4 screws that hold lcd from chasiss. you can remove lcd now.
4. remove 3 screws under keyboard.
5. remove all screw on the back of your laptop.
6. remove upperchassis.
7. remove 2 screw that hold motherboard from lowerchasis.
8. take motherboard out from lowerchasiss.
9. now you can see the thermal fan.

SOURCE: i need the boot priority order for an acer aspire

Restart the computer, and enter BIOS SETUP mode, and view/change the boot-priority order.