Hi and welcome.
The LPIA architecture is no more supported in Lucid. Since it was very similar to i386, it just had no meaning to exist.
The ubuntu version to install depends on your needs.
If you use your netbook just for web browsing, email, etc, then I think the netbook version is the best choice. On the other hand, if you use your netbook for more advanced work, then I'd suggest the normal version.
Personally, I use the normal version because I don't want to change my habits and I simply love the standard gnome desktop.
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