New to eclipse Challenges??

As a first time user of Eclipse. among the difficulties I have found, ( I used Netbeans before)
not able to checkout code from the repository. I didn't know I could incorporate subclipse to do this. Thanks to Ben now its now fine.
Memory requirements
it looks like Eclipse is a bit memory hungry. I am using a 256Mb and when I fire Eclipse, well its a pain to code. I plan to upgrade to 512Mb but I feel like 1Gb would be the ultimate.

Perspectives: these can confuse. i haven't had an easy time deciding what perspective to use but thanks to eclipse developers, its looks they always suggest the best perspective depending on the type of project.
Ant- Am not sure if other developers have experienced this problem. sometimes when I try to package a module, Ant just freezes and you cannot do anything, if you restart eclipse, the build file you were working on gets corrupted.am using Apche Ant 1.7.0
WIKI although the openmrs Wiki may not give a lot of details about how to accomplish many of the tasks needed, I must admit that almost every difficulty you come across will have a mention there. i have wasted substantial amounts of time when I could have been sorted by the Wiki ( am wiser now)

Css/Dtd

I have been skimming through the Openmrs source code. I am wondering if there is a document that explains the various components of Openmrs and how they interact, like a schematic diagram

In using JSP, is there a predefined CSS and/or Dtd files that are being used and where can one find their definations?
In my conversation with Ben, I have the impression that there are a number of methods that are already implemented in openmrs that one would like to borrow from but the structure of openmrs seems deep to understand in a short time and develop at the same time. for developers who are used to almost procedural top-bottom approach, developing for Openmrs would be slowed down majorly by the mind set. Even if one is good in Java, these skills may prove difficult to use.