I'm reading your question as about page ranking (which is important), not page rank (which is not).

1. Nope - except in local searches; for example, a .co.uk site will fare better in UK searches (host country makes a difference, too).

2. Getting quality links, eg from a quality directory is generally safer than exchanging links, which nees to be with related sites, and with quality sites only. Careless linking costs lives - site lives, not people's ;)

3. Validation does not directly affect page ranking. But checking your validation, just like checking your site for Google sitemaps or adsense, can throw up errors and problems you never realised you had. So it is worth thinking about. Xenu is probably a better way to find errors that may affect spidering and therefore ranking - it's the best way to check navigation.

ya thanx buddy, but coming to my second ques again, i'm not still clear abt it. lets say if i have a website about "money making from home". so which option is better from these:

1) exchange links with a site about "money making from home"

2) simply get a link back to my site from that site, contacting its webmaster, but not providing a link from my site to his site.

i think its clear now..its: link exchange vs one way link

Generally, one way linking is 'safer', as SEs will rarely penalize you for links TO your site, but will certainly penalize you if you choose to link to a bad neighborhood (even if you didn't realise it was bad).

But linking is what the web is all about, and many people believe that sites with no outbound links should also be penalized, though I've seen no evidence. But be careful where those links go.

As for 'value', in general, a link is a link, regardless of whether you link back or not. I have seen some amazing mathematical calculations 'proving' that linking back reduces the value of the inbound link - but unless you have the SE algorithm in your and you fret over 0.0001%, I'd not lose sleep over that.

alrite, 1 more thing i wud like to kno..

shud i get links from a site's homepage (having a similar contant to mine) or any page (having relevant content, of course) on that site?
which on eis more beneficial?

thanx