I want to update my software to 10.6, will it delete everything I have saved?

Your profile shows you have 10.6.3 - but your question asks about updating to 10.6? That would not be an update - that would be reverting back.... If you mean updating to the latest version, which is 10.6.7, then the answer is: No, it will not delete anything.

You should download the combo update here:

http://support.apple.com/kb/DL1361

Then unplug every peripheral except keyboard and mouse.

Run Verify disk in Disk Utility (Applications folder > Utilities)

Install downloaded update

Run Repair Permissions in Disk Utility

Restart computer again

You should be fine.

Note: some third party apps may need to be updated to be compatible with OS 10.6.7 - you will need to check their websites if you encounter any problems.

Hi,

Seeing you have added almost every tag there is I will answer the iChat Bit.

Between OS 10.6.3 and OS 10.6.7 there are no changes to iChat (Although any updates, when they come, are included in the OS Updates).

iChat 5.0.3 that you have can open any iChat files created from version 1 onwards.

Of course to a certain extent How and what you are Updating may bear looking at further.

If it is not the computer that is On 10.6.3 then it has to be an Intel.

You should not use Erase to Update/Upgrade it from Leopard if that is what you are doing.

Installing Snow Leopard (10.6) over Leopard (10.5.x) works in a similar fashion to doing a regular update in that it acts more like an Update - leaving your Home folder intact. (It is very wise to have a back up though)

As babowa says What apps then work will depend.

Some on whether they are written in Universal code (PPC and Intel) Or at least Intel Only which is what Snow Leopard is.
Some will not work as some of the underlying processes have moved and the app will not be looking in the right place.

Some will not work as the processes they are accessing have been updated beyond what the app can use.

8:25 PM Saturday; April 30, 2011

Please, if posting Logs, do not post any Log info after the line "Binary Images for iChat"

 G4/1GhzDual MDD (Leopard 10.5.8)
 MacBookPro 2Gb( 10.6.7)
, Mac OS X (10.6.7),
"Limit the Logs to the Bits above Binary Images."  No, Seriously

For the Points

7:09 PM Tuesday; February 19, 2013

Please, if posting Logs, do not post any Log info after the line "Binary Images for iChat"

 iMac 2.5Ghz 5i 2011 (Mountain Lion 10.8.2)
 G4/1GhzDual MDD (Leopard 10.5.8)
 MacBookPro 2Gb (Snow Leopard 10.6.8)
 Mac OS X (10.6.8),
 Couple of iPhones and an iPad
"Limit the Logs to the Bits above Binary Images."  No, Seriously