IMO most of those games (from the 10 game TRU bundle) are pretty bad.
Its an excellent deal for young children (and this is TRU I suppose).. because they don't really mind crappy games allot of the time. You get a console and LOADS of games for a reasonable price. But I certainly wouldn't be interested. I wouldn't even be interested in more then 2-3 of those games, and not even that interested in thos. Quantity is nothing to me without quality.
I suppose you could probably sell those 10 games for about £135 on ebay if you sold them singley, maybe £135, but it'd be a bit of an annoyance and you'd still only end up with the GameCube for £115 (you can buy it online by itself for £120).
I'd prefer to go with one of the better 4 game £199 bundles at TRU, I think I saw one with SMS, SFA, SSB:M and Eternal Darkness.. or something like that anyway, 4 quality games.. now that's a bit better IMO. If you sold those you'd likely get £100 on ebay and so you'd have the GameCube for £99. But in the end these are all simply TRU bundles, any losses are to TRU themselves.
As far as XBox goes. I just can't believe MS are selling XBox for £199 with those 4 free games, I mean Halo is the best game for the console and Splinter Cell is there biggest new title.
You could sell those 4 games one ebay for £100 easily, maybe even £110, then you have the XBox for only £99.99, possibly even £90.99! Considering how much it costs MS to make the XBox that is one hell of a low price! And this is a bundle direct from MS not any single store.
I'm really not suprised that XBox is getting really good sales in the U.K right now, they'e almost giving the console away.