Hello!
LimeWire 2.5.2 is still beta and not a replacement for the current 2.4.4 release.Wait until the 2.4.4 version gets replaced with a new full version of 2.5.x.
Now to your problems!
Yes it is true that Apple no longer updates the Java for classical Mac OS but the Mac version of LimeWire will function great anyway.LimeWire actually runs slightly better on the Mac platform then on Windows that have had a lot of problems especially with Windows XP and the JRE 1.4.
The problem with Mac's and Java is that as a mac user you are more dependant on more RAM to get a pleasent experience when running Java apps.Java really hates Virual Memory and advanced Java apps that runns when VM is turned on will run terribly slow and crash often.So my recommendations to you would be the following:
Update yor MRJ (Mac OS Runtime For Java) to the latest version which is 2.2.5 available trough Apple's website(Do not install the java that are included in the LW installer instead turn that offer down)
http://www.apple.com
And after you have installed it assign 30000k of preffered memory to it.
Then upgrade your machine so that you have atleast 320MB of physical RAM which is the amount that I have.Why exactly 320MB? welll that is because that is the limit at which Apple recommends that you turn off Virtual Memory.Once you have done that and turned off VM then LimeWire will work like a charm and almost never crash on you.
As far as the installation problem is concerned try downloading and install the 2.4.4 version and install it but refuse the Java to be installed
If the installer refuses to install something then just try to assign the installer more memory add about 1000k and it will probably install just fine.